Every PC user knows perfectly well that a computer consists of a monitor, keyboard, mouse, speakers and a system unit. But it's clear that this is just the tip of the iceberg. This, so to speak, is just one side of the coin. If we look inside the system unit and other components of the computer, then we will find a huge amount of details, thanks to which, in fact, it works.
The most basic, of course, is system unit.
In general, he is directly a computer that performs hundreds of thousands of operations. If we replace the monitor, keyboard or mouse, then it will become simply more convenient for us to watch movies, listen to music, type texts, and so on, but the PC parameters will remain the same. Everything that is displayed on the monitor and sounds in the speakers depends on what is inside. The internal details of the system unit determine the capabilities of the system as a whole.
The computer system unit consists of: video card, hard disk, RAM modules, coolers, processor, motherboard and many other parts. Let's consider the important details and their functions in more detail.
Motherboard
- this is the basis of the entire system unit.
This is the board to which all the other parts of the mechanism are attached: video card, processor, hard drive, etc. Because of this, it has a corresponding name. It provides the vital functions of other parts. The main function of the motherboard is to connect the rest of the parts so that they work as one piece. If you open the cover from the system unit, you will immediately notice it.
CPU
- this is the so-called heart of the computer.
It is the processor that executes all those commands that the PC user sets. The speed and capabilities of a computer depend on how powerful the processor is. The processor is located on the motherboard in a special socket called the "CPU socket" or "socket".
Cooler... This part is located just above the processor.
The cooler is a small heatsink with a fan that dissipates heat and thus cools the processor. This is a very important detail, because if the processor overheats, the computer will shut down. And this will quickly lead to PC breakdown.
Winchester or hard drive
Is a device that stores all the information on your PC.
It goes without saying that the larger the volume of the hard disk, the more information the computer can hold. The location of the hard drive in modern computers is slightly different from older computers. They are now connected using the interface. As a rule, hard drives often overheat too, and therefore, for a longer life of the computer, install another small cooler near the hard drive, which will be enough to avoid repairs.
Video card - the part of the computer responsible for the speed of video processing.
In modern computers, the video card is installed to the motherboard through the PCI-Express slot. There are also motherboards that have multiple PCI-Express slots, this naturally improves the picture, and makes the graphics subsystem more powerful in general. But in general, a regular video card is enough for the average user. Powerful video cards are necessary for those who, directly, work with graphics, or simply those who like to play toys with a clearer picture in order to feel the whole atmosphere of the game. Also, each computer has a sound and network card. Their names themselves speak for their functions in the PC.
RAM modules Is RAM in other words.
RAM temporarily stores data that the processor needs to perform an operation. At the end of such processes, for example, after closing a particular operation, the data from the RAM is immediately deleted. The speed of the RAM, or rather the access to it, is much higher than the speed of access to the hard drive. This helps you get virtually instant access to the information you need. There are different models of RAM, and therefore the connectors for them on the motherboard also exist.
These are, of course, not all the parts that make up a computer. In order to expand the capabilities of your PC, various TV tuners, modems and more are also installed. It already depends on the wishes of the user.
And, of course, in order for all this to function, you need power Supply, which will give life to all this "iron".
In this lesson I will talk about the device of a computer: what a PC consists of, what function does each of its parts perform.
Consider the hardware ("hardware"):
- system unit - that large box that stands on your table or under the table, on the side of it, etc. It contains all the main components of the computer.
- peripherals - additional components such as monitor, keyboard, mouse, modem, scanner, etc.
What does computer consist of
The system unit in the computer is the "master" one. If you carefully unscrew the screws from its back wall, remove the side panel and look inside, then only in appearance its structure will seem complicated. Now I will briefly describe its structure, and then I will characterize the main elements in the most understandable language.
The system unit contains the following elements (not necessarily all at once):
- Power Supply
- Hard disk drive (HDD)
- Floppy disk drive (FDD)
- CD or DVD drive (CD / DVD ROM)
- Connectors for additional devices (ports) on the back (sometimes on the front) panel, etc.
- The motherboard (it is more often called the motherboard), which, in turn, contains:
- microprocessor;
- mathematical coprocessor;
- clock pulse generator;
- memory chips (RAM, ROM, cache memory, CMOS memory)
- controllers (adapters) of devices: keyboards, disks, etc.
- sound, video and network cards;
- timer, etc.
All of them are connected to the motherboard using connectors (slots). We will consider its elements in bold below.
And now, in order about the system unit:
1 . With the power supply, everything is clear: it powers the computer. I will only say that the higher its power rating, the steeper.
2. A hard disk drive (HDD) is called a hard disk drive by the common people.
This nickname arose from the slang name for the first 16KB hard disk drive (IBM, 1973), which had 30 tracks of 30 sectors, coincidentally coinciding with the 30/30 caliber of the famous Winchester hunting rifle. The capacity of this drive is usually measured in gigabytes: from 20 GB (on older computers) to several terabytes (1TB \u003d 1024 GB). The most common hard drive capacity is 250-500 GB. The speed of operations depends on the rotational speed (5400-10000 rpm). Depending on the type of connection between the hard drive and the motherboard, ATA and IDE are distinguished.
3. A floppy disk drive (FDD) is nothing more than floppy disk drive... Their standard capacity is 1.44 MB with a diameter of 3.5 "(89 mm). As a storage medium, magnetic disks use magnetic materials with special properties that allow fixing two magnetic states, each of which is assigned binary digits: 0 and 1.
4 . Optical disc drives (CD-ROM) come in different diameters (3.5 "and 5.25") and capacities. The most common of them are 700 MB. It happens that CDs can be used for recording only 1 time (then they are called R), and it is more profitable to use rewritable RW discs.
DVD originally transcribed as Digital Video Disk. Despite the name, DVDs can burn anything from music to data. Therefore, in recent years, another decoding of this name is increasingly common - Digital Versatile Disk, loosely translated as “digital versatile disk”. The main difference between DVDs and CDs is the amount of information that can be recorded on such a medium. DVD-disc can be recorded from 4.7 to 13, and even up to 17 Gb. This is achieved in several ways. First, a laser with a shorter wavelength is used to read DVDs than to read CDs, which has significantly increased the recording density. Secondly, the standard provides for the so-called double-layer discs, in which on one side the data is recorded in two layers, while one layer is translucent, and the second layer is read "through" the first. This allowed data to be written to both sides of DVDs and thus double the storage capacity, which is sometimes done.
five . Other additional devices ( mouse, printer, scanner andother). Connection is made through ports - special connectors on the rear panel.
The ports are parallel (LPT), serial (COM), and universal serial (USB). The serial port transfers information bit by bit (more slowly) over a small number of wires. A mouse and modem are connected to the serial port. The parallel port transfers information simultaneously over a large number of wires corresponding to the number of bits. A printer and an external hard drive are connected to the parallel port. The USB port is used to connect a wide variety of peripherals, from mouse to printer. It is also possible to exchange data between computers.
6. The main computer devices (processor, RAM, etc.) are located on motherboard.
Microprocessor (easier - processor) - the central unit of the PC, designed to control the operation of all units of the machine and to perform arithmetic and logical operations on information.
Its main characteristics are bit depth (the higher it is, the higher the performance of the computer) and clock frequency (largely determines the speed of the computer). The clock frequency indicates how many elementary operations (cycles) the processor performs in one second.
The market respects Intel Pentium processors and its economy version Celeron, and also values \u200b\u200btheir competitors - AMD Athlon with the economy version Duron. Intel processors are characterized by high reliability, low heat generation and compatibility with all software and hardware. And AMD shows faster graphics and gaming performance, but less reliable.
Computer memory can be internal and external. External memory devices include the already discussed HDD, FDD, CD-ROM, DVD-ROM. Internal memory includes permanent memory (ROM, ROM English), operational memory (RAM, RAM English), cache.
ROM is designed to store permanent program and reference information (BIOS - Basic Input-Output System - basic input-output system).
RAM is fast and is used by the processor for short-term storage of information while the computer is running.
When the power supply is turned off, the information is not saved in RAM For the normal functioning of a computer these days, it is desirable to have from 1 GB to 3 GB of RAM.
CACHE memory is a super-fast random access memory.
CMOS memory - CMOS RAM (Complementary Metall-Oxide Semiconductor RAM). It stores computer configuration settings that are checked each time the system is turned on. To change the computer configuration parameters, the BIOS contains the computer configuration program - SETUP.
Sound, video and network cards can be both built into the motherboard and external. External boards can always be replaced, whereas if the integrated video card fails, the entire motherboard will have to be replaced. For video cards, I trust ATI Radeon and Nvidia. The higher the amount of video card memory, the better.
Peripherals
The computer consists of 6 groups of keys:
- Alphanumeric;
- Controls (Enter, Backspace, Ctrl, Alt, Shift, Tab, Esc, Caps Lock, Num Lock, Scroll Lock, Pause, Print Screen);
- Functional (F1-F12);
- Numeric keypad;
- Cursor control (-\u003e,<-, Page Up, Page Down, Home, End, Delete, Insert);
- Function indicator lights (Caps Lock, Num Lock, Scroll Lock).
Mouse (mechanical, optical). Most programs use two of the three mouse buttons. The left key is the main one, it is controlled by the computer. It plays the role of the Enter key. The functions of the right key depend on the program. In the middle there is a scroll wheel, which you quickly get used to.
Modem is a network adapter. It can be both external and internal.
The scanner automatically reads from paper carriers and enters into the PC any printed texts and images.
The microphone is used to input sound into the computer.
(display) is for displaying information on the screen. Most often, modern PCs use SVGA monitors with a resolution (the number of dots located horizontally and vertically on the monitor screen) 800 * 600, 1024 * 768, 1280 * 1024, 1600 * 1200 with up to 16.8 million colors.
Monitor screen sizes range from 15 to 22 inches diagonally, but most commonly 17 inches (35.5 cm). Dot (grain) size - from 0.32 mm to 0.21 mm. The smaller it is, the better.
PCs that are equipped with television monitors (CRTs) are no longer as popular. Of these, preference should be given to monitors with low radiation (Low Radiation). Liquid crystal displays (LCDs) are safer and most computers have such a monitor.
Designed for printing text and graphics. Printers are dot matrix, inkjet and laser. In dot matrix printers, the image is formed from dots in an impact manner. Inkjet printers in the print head instead of needles have thin tubes - nozzles through which the smallest droplets of ink are thrown onto the paper. Inkjet printers can also print color by mixing base colors. The advantage is high print quality, the disadvantage is the danger of ink drying, the high cost of consumables.
Electrographic imaging is used in laser printers. The laser is used to create an ultra-thin light beam that traces the contours of an invisible dotted electronic image on the surface of a pre-charged photosensitive drum. After the development of the electronic image with the powder of dye (toner) adhering to the discharged areas, printing is performed - the transfer of toner from the drum to the paper and the image is fixed on the paper by heating the toner until it melts. Laser printers provide the highest quality printing at high speed. Color laser printers are widely used.
Sound speakers output sound. The sound quality depends - again - on the power of the speakers and the material from which the enclosures are made (preferably wood) and its volume. An important role is played by the presence of a bass reflex (hole on the front panel) and the number of frequency bands (high, middle and low speakers on each speaker).
In my opinion, USB flash drives have become the most versatile means of transferring information. It is a miniature device in size and weight less than a lighter. It has high mechanical strength, is not afraid of electromagnetic radiation, heat and cold, dust and dirt.
The most sensitive part of the drive is the connector covered with a cap. The sizes of these devices range from 256 MB to 32 GB, which allows you to select the drive of the right capacity, in accordance with the needs. Thanks to the interface, the USB drive can be connected to any modern computer. It works with Windows 98SE / Me / 2000 / XP / Vista / 7, Mac OS 8.6 ~ 10.1, Linux 2.4 operating systems. In Windows, you don't even need to install any drivers: plug it into a USB port and go.
It is needed to enter a dynamic image into a computer and sound (for communication and the possibility of creating teleconferences).
Uninterruptable power source needed in case of an emergency power outage.
Fuff, well, in my opinion, that's all the main thing that I wanted to tell you about the hardware of the computer, the so-called hardware.
The article "Computer device" was written quite a long time ago. Therefore, if you find an error or find some inaccuracy, please write about it using the comment form. We will be very grateful to you!
Computers can vary in many ways, both in size and in their inherent capabilities. Integration of computers into other devices is no longer a novelty, they can be built into cars, household appliances and much more, but in turn, such computing mechanisms perform only tasks defined by the developer.
There are a lot of types of devices, which can rightfully be called computers, and every year there are only more such computer devices presented to the world by developers, and the devices themselves can be logically divided into certain types of computer groups.
Computer types and computer types
What is a type of computer? This is a group of computers that have similar functionality or method of use, and a certain computer technology is considered a type of computer and computing devices that are usually similar in appearance, just like the type of computer, have their own distinctive capabilities. For example, a personal computer is a type, and types of PCs are computers that are used by a person for personal purposes: candy bar, tablet, nettop, etc.
If in the last century computers could be both analog and digital, then today only digital computers remain relevant. It will be about exactly this type of technology as a digital computer, they are used today.
In addition, it is wrong to divide computers according to the classification of the last century, the line between microcomputers and minicomputers is no longer noticeable, and other devices are already called such, and mainfream is only roughly equated to today's servers.
Personal computers
If we are inclined to believe that the world is ruled by personal computers, then to a greater extent it is, the only thing is that they do not rule in the literal sense, just their number is the largest. A personal computer, also referred to in abbreviated form as a PC, relies on working with a person directly, that is, a computer makes it possible to obtain understandable information for a person. PCs can be represented by both types of desktop computer systems - Desktop, and portable computer devices, some of which you can not only take with you on the road, but also put in your pocket. In turn, personal computers can be divided into portable and stationary devices.
Types of stationary personal computers
The type of stationary PC means a computer that has a permanent place, which actually serves as, say, a computer desk and does not imply a frequent change of place. Such computers can also be called workstations, because there is enough computing power to perform a certain job, that is, intensive calculations.
There are three main types of such devices:
1. Desktop computers or desktops
The most highly productive representatives of personal computers are desktops. A desktop computer is called this because the place of placement is a writing, and later, after some changes, a computer desk.
The main component here is the system unit, which is usually a rectangular box, most often located either at the top of the table or at the bottom. A monitor, keyboard and mouse are connected to the system unit, all these components interact with each other.
The system unit is a modular device, which means the ability to replace each component - a module, independently, thereby changing the configuration for yourself.
2. Nettops
3. Monoblocks
Monoblock is also a stationary computer, but without a visible system unit. The frame for this type of computer as a monoblock is one common case with a monitor. All components are located in the rear part, behind the display, which creates a certain aesthetics for working at a computer. What is a candy bar and an all-in-one computer, you can clarify in the article of the same name.
Types of portable personal computers
What is a portable device? Portable means portable, and in our case, the mobility of computers is provided by a smaller size and a capacious battery compared to a desktop computer. In most cases, this type of computers to increase the hours of battery life limits itself in performance, but these capabilities are enough to perform certain, in fact, like for any computer, computing operations.
1. Laptops and their closest relatives, netbooks
Laptops are computers that can be easily carried, have the ability to operate independently, which is possible thanks to the battery, like other types of portable computers. In addition, a distinctive feature from stationary computers is made by the presence of combined components, a keyboard display in one case. And the ability to fold makes them even more compact.
Netbooks are all the same laptops, which are not only smaller and have longer battery life, but also lower performance, which prevents them from using resource-intensive applications.
These knee-high types of computers, based on the book principle of closing and opening, provide, although not high, but sufficient performance to meet the needs of the user. What is a laptop - this article will be able to create a general idea of \u200b\u200ba laptop, netbook and other folding computers.
2. Tablets and tablet laptops
Tablets are portable computers that share the needs of users in PDAs with smartphones, in one case, the computing potential for browsing the Internet, video and listening to music, the basis here is such an input device as a touchscreen display - Touchscreen (touchscreen), are real helpers, and in some situations it is more convenient than a laptop due to its smaller size.
Tablet laptops, in addition to a touchscreen, just like a laptop, have a keyboard and, depending on the model, can either fold or slide out.
The main task of this type of portable device is precisely the output and use of the Internet, although there are basic multimedia capabilities. For such mini computers, battery life is more important than performance when compared to the same Desktop.
3. Pocket types of computers and smartphones
If earlier the differences between smartphones and PDAs (pocket personal computers) were really noticeable, now an average statistical smartphone performs the same functions, and the popularity of PDAs is not the same as before, but this type of computer still has its users.
Just like other types of computers, which are representatives of portable devices, depend on the battery life. They are rather small in size, which favorably affects the ability to have them always at hand, which is the opposite of performance. Due to the lower resolution, it is possible to use such devices for viewing videos and photos, even if they are not the best players, but they are not deprived of this opportunity, and the photo and video shooting functions are a good plus.
These devices are battery operated and are sized to carry them with you at all times. The main difference between today's models of smartphones and PDAs is that the former will perform, in addition to the computing function, the function of the phone. Modern models without fail have such an input device as a touchscreen display.
Computing servers
This type of computer as a computing server underlies the work of local networks and the Internet in general. All network operation is based on the server operation of computers, each of the Internet resources, its files, and any type of information on the network is located on the storage device of some type of server.
Undoubtedly, high performance of server versions of computers is very important, but not so much as their reliability. Computers performing the task of the server, first of all, must have very high reliability and work without exception for the entire service life, because the information stored on the server must be constantly available, and in no case can it be lost. The use of backups is becoming mandatory for these types of computer solutions.
Servers can process a large amount of information, and parallel processing of information is the basis of computations. Therefore, server versions of computers are aimed at the development of multiprocessing and their multicore.
In general, almost any computer can be a server, it does not have to be cumbersome as many people think, because its function is to serve other computers in the network, it is their information source. For example, a nettop can become not a bad home server, but using the functionality of the system unit, it can be easily used as a hosting for your blog. In terms of functionality and size, the servers are comparable to the type of computer of the outdated classification - mainfremes.
Supercomputers
The computers with the highest performance are called supercomputers. Such computing facilities are ultra-fast types of computers. It is a multi-computer and multiprocessor complex occupying large rooms with shared memory and other devices that are also common.
Such computers are characterized by multiprocessing processing of many operations simultaneously - trillions of operations per second. They use the capabilities of such computers for very important tasks, at the state, world level. In modeling complex natural phenomena, various effects of chemical, biological or nuclear weapons, such a supercomputer makes it possible to predict as closely as possible, for example, a cataclysm. Such computers can occupy entire buildings, government agencies, scientific computing and research centers.
The structuring of the elements, as well as the parallel and vector organization of the computational process, determines the ability of each system element to deal with its part of the task, in fact, the concept of a cluster appeared.
What other types of computers are there
Types of computers are provided to mankind by a large number of types and are not limited to the usual clone computers. Clone computers are, simply put, a lineup.
Sometimes the presence of such a computer near by is not clear to everyone, for example, a payment terminal or an ATM is one of the types of computers, and it is stationary and personal.
Modern game consoles are also computers, they carry a computer component, and besides the main function of the game, they cope with other entertaining tasks. Household devices have microprocessors, which, in fact, are also part of a computer.
Perhaps very soon, in our home, and not in a science fiction film, there will appear such a type of computer as a robot, which will also perform certain functions. Every year new representatives of computers appear, their capabilities are only expanding, and if you bring a little fiction into the material, then the main thing is to prevent the evolution from robotics to the appearance of a race of robots, which will become a worthy competitor to humanity.
The main computer devices "live" in the system unit. These include: motherboard, processor, video card, RAM, hard drive. But outside of it, usually on the table, there are also no less important computer devices. Such as: monitor, mouse, keyboard, speakers, printer.
In this article, we will consider what does computer consist ofhow these devices look, what function they perform, and where they are.
System unit.
In the first category, we will analyze those devices, or they are also called components, which are "hidden" in the system unit. They are most important to his work. By the way, you can immediately look into the system unit. This is not difficult. It is enough to unscrew the two bolts on the back of the system unit and move the cover to the side, and then we will see a view of the most important computer devices, in order of which we will now consider.
The motherboard is a printed circuit board that is designed to connect the main components of a computer. Some of them, for example, a processor or video card, are installed directly on the motherboard itself in the socket provided for this. And the other part of the components, for example, a hard drive or a power supply, is connected to the motherboard using special cables.
A processor is a microcircuit and at the same time the "brain" of a computer. Why? Because he is responsible for all operations. The better the processor, the faster it will perform these very operations, respectively, the computer will work faster. The processor, of course, affects the speed of the computer, and even very strongly, but the speed of the PC will also depend on your hard disk, video card and RAM. So the most powerful processor does not guarantee a high speed of the computer if the rest of the components are already outdated.
3. Video card.
A video card or in another way a graphics card is designed to display images on the monitor screen. It is also installed in the motherboard, in a special PSI-Express connector. Less often, a video card can be built into the motherboard itself, but its power is often enough only for office applications and working on the Internet.
Random access memory is such a rectangular bar, similar to a cartridge from old game consoles. It is intended for temporary storage of data. For example, it stores a clipboard. We copied some text on the site, and immediately it got into the RAM. Information about running programs, computer hibernation and other temporary data are stored in RAM. A feature of the RAM is that the data from it is completely deleted after the computer is turned off.
Hard disk, unlike RAM, is designed for long-term storage of files. In another way, it is called the Winchester. It stores data on special plates. Also recently, SSD drives have spread.
Their features include high speed of work, but there is immediately a minus - they are expensive. A 64 gigabyte SSD will cost you the same price as a 750 gigabyte hard drive. Can you imagine how much an SSD for several hundred gigabytes will cost. In, in! But do not be upset, you can buy a 64 GB SSD drive and use it as a system drive, that is, install Windows on it. They say that the speed of work increases several times. The system starts up very quickly, the programs fly. I plan to upgrade to an SSD and store my regular files on a traditional hard drive.
The drive is needed to work with disks. Although it is already much less commonly used, it still does not interfere with stationary computers. At least the floppy drive is useful for installing the system.
6. Cooling systems.
The cooling system is the fans that cool the components. Usually three or more coolers are installed. Necessarily one on the processor, one on the video card, and one on the power supply, and then as desired. If something is lukewarm, it is advisable to cool it. Fans are also installed on hard drives and in the case itself. If a cooler in the case is installed on the front panel, then it takes heat, and coolers installed on the rear compartment supply cold air to the system.
The sound card outputs sound to the speakers. It is usually built into the motherboard. But it happens that it either breaks down, and therefore is bought separately, or initially the quality of the standard PC owner does not suit and he buys another sound. In general, a sound card also qualifies for this list of PC devices.
The power supply is needed in order for all the above-described computer devices to work. It provides all the components with the required amount of electricity.
8. Case
And in order for the motherboard, processor, video card, RAM, hard drive, floppy drive, sound card, power supply and possibly some additional components to be shoved somewhere, we need a case. There it is all neatly installed, twisted, plugged in and begins daily life, from on to off. The required temperature is maintained in the housing, and everything is protected from damage.
As a result, we get a full-fledged system unit, with all the most important computer devices that are needed for its operation.
Peripherals.
Well, in order to fully start working on a computer, and not look at the "buzzing" system unit, we need Peripherals. These include those computer components that are outside the system unit.
The monitor itself is needed to see what we are working with. The video card feeds the image to the monitor. They are connected to each other with a VGA or HDMI cable.
The keyboard is designed to enter information, well, of course, what a job without a full keyboard. Type text, play games, surf the Internet, and everywhere you need a keyboard.
3. Mouse.
The mouse is needed to control the cursor on the screen. Drive it in different directions, click, open files and folders, call various functions and much more. As well as without a keyboard, without a mouse anywhere.
4. Columns.
Loudspeakers are needed mainly for listening to music, watching movies and playing games. Who else today uses speakers more than ordinary users reproduce them daily in these tasks.
A printer and a scanner are needed to print and scan documents and everything else you need in the field of printing. Or MFP, multifunctional device. It will be useful to all those who often print, scan, make photocopies and perform many other tasks with this device.
In this article, we have only briefly covered the main computer devices, and in others, the links to which you see below, we will consider in detail all the most popular peripheral devices, as well as the components that are part of the system unit, that is, components.
Enjoy reading!
Hello to all my blog readers! Today there are many devices that bear the proud name "computer". The types of computers every year become more diverse, more interesting, manufacturers are doing more, and also adding new functions for the convenience of the user. This article will help you understand this variety, thereby you will find out what computers are.
Desktop computers... To be called a desktop computer, it must have a system unit, monitor, keyboard and mouse - this is the minimum set. A printer, scanner, speakers, or peripheral equipment can often be found nearby.
Also, a novice user may be confused by the different shape and size of the system unit, with the same composition of the minimum components, which were mentioned above.
So, system blocks are:
- Classic, vertical (tower). They can be of regular medium size (midi-tower) or high (full-tower). Full-towers are rare today, a common system unit is a midi-tower.
- Horizontal system blocks. This type is almost never found, it was popular at the dawn of the computer era, usually such a system unit was located right under the monitor.
- LCD PC slim-desk. It is customary to call modern system units 2-4 times smaller than usual with such a terrible English phrase.
There is also a version of a desktop computer without a system unit at all, but they are not yet common and are rather an exception. In this case, all "insides" are located in the monitor. This, of course, is very aesthetically pleasing, convenient, we take up little space, but very expensive compared to conventional desktop computers. I think over time the price will drop and the average user will no longer pay attention to the price of this computer and I would also like to note that these computers are made with a touchscreen screen.
Laptop... The name comes from the English "Notebook" (Russian notebook), since it is the notebook that resembles this type of computers in the "open" form. Another, less common name in the post-Soviet space is a laptop, from the English "LapTop" (lap \u003d knees of a sitting person, top \u003d top). The name comes from the "place" on which a computer usually stands in the absence of a table: on its knees.
Until recently, laptops lagged far behind their desktop counterparts in power and were often used only as an addition to a home computer. Today, many users have abandoned bulky desktops in favor of compact and mobile laptops. A modern laptop offers reasonably high performance, a wide range of sizes, colors and a fairly long battery life, which is especially useful for a mobile device.
Netbook... In fact, this is a laptop, but with some of its own characteristics. First, they are usually smaller than a laptop. Secondly, their battery life is greatly increased, however, this is done to the detriment of performance (and there is no other way). Thirdly, they are cheaper. In general, the performance is reduced not only to reduce power, but also to reduce the cost. Initially, these computers were intended solely as a means of accessing the Internet and performing only minimal actions other than that. Hence the name came from: in Russian "Net" - a network. 
Tablet PCs or TabletPCs... This category is just gaining its popularity right now. Such a computer is just a small touch screen. In TabletPC, due to the touch screen, a keyboard and mouse are not required (although they can be used if the user wishes), usually the tablet computer monitor is adapted to work with fingers. In some models, you can also find sliding or folding keyboards. Tablets are not very powerful, but this is not required of them.
Their main task is to allow the user to access the Internet, in addition, you can watch a movie, listen to music, or anything else that does not require a lot of power, which, in principle, is convenient to do on such a device. But the main task is to provide the owner with comfortable Internet access, without burdening him with a large and heavy bag. The most important indicator for a tablet computer is battery life, since this is mainly a mobile device, usually this indicator is at their height. It is in this category that the Apple iPad, so desired by many users, belongs.
Pocket computers or PDAs (PDAs)... Such a computer is often called "handheld", it earned this name due to its size. This type of computer is a small device with a touch screen, for the use of which there is usually a stylus (a small special pointer) in the kit. It is not convenient to use fingers on this device (due to the small size of the elements on the screen) or completely impossible due to the design features of the display.
Also, the device can be equipped with a folding push-button keyboard. Usually PDAs do not have access to the Internet and are designed to solve some problems locally. It should be noted that smartphones, in fact, are a logical continuation of the evolution of pocket computers. Since they differ only in the ability to make calls, which means they can get to the Internet.
The main feature of the game console is the lack of a screen. Therefore, it is also a "prefix" that is "attached" to the TV. Previously, they could only give an opportunity to play and did little to resemble a computer. Modern models provide much more opportunities: to play, and watch a movie, and listen to music, and even go online.
Inside, they are all the same computer: they have a central processor, random access memory (RAM, RAM), and a hard disk (ROM, ROM). Outside, they have a drive for laser discs (cd, dvd, blu-ray), as well as connectors for connecting external devices (for example, USB and Ethernet network connector). But do not forget that games remain their main task. Now there are such models of consoles that can be played even without a TV, since it has its own small screen.
As you understand, there are a lot of types of computers. But I am sure that an even more interesting and useful device for humans will appear in the near future.
P.S. Today for dessert - a computer, which is slightly larger than a credit card. It's nice to see where a person is going.
