What are the functions of computer peripherals?

Monitor —— (English: Screen, monitor), also known as display screen, screen and fluorescent screen, is an electrical appliance used to display images and colors. Its main function is to let us see what the computer is running, the one we look at when using the computer. Described by weight: CRT-cathode ray tube display (the heaviest part outside the computer mainframe, of course, excluding other printers, scanners and so on), LCD-liquid crystal display (as mentioned above, only the heaviest weight becomes the fourth lightest-before it was No.1 earphone/mouse, No.2 keyboard, No.3 speaker). Host: including read-in devices (CD-ROM, Floppy Disk, USB flash drive, graphics card, hard disk, motherboard, CPU, radiator, power supply, network card, sound card, memory, etc.) CD-ROM: Taiwan Province is a CD-ROM, which is a machine used by computers and electronic game machines to read and write CD contents, including recording and non-recording, and is mainly used to read and burn CDs, which can be divided into DVD-ROM \ CD-ROM. The first floppy disk was developed by IBM in 1971, with a diameter of 8 inches. With the development of hardware technology and the need of use, a 5.25-inch floppy disk has been derived and widely used in Apple II, IBM PC and compatible computers. Apple began to use 3.5-inch floppy disk on Mac in 1984, when the capacity was less than 1MB. Later, it was replaced by Sony's 3.5-inch floppy disk with a capacity of 1.44MB. This kind of floppy disk was popular from 198s to 199s. Until 2, the 3.5-inch floppy disk was still one of the popular computer devices, but now it is basically eliminated. USB flash drive: it is the corresponding device of USB socket. It is a medium that uses flash memory to store data, usually using USB plug. Usually, flash drives are small, light, hot-swappable and can be written repeatedly. After its appearance, it quickly popularized and replaced traditional floppy disks and floppy drives. To access the data of the flash drive, you must connect the flash drive to the computer; Whether it is directly connected to the computer's built-in USB controller or a USB hub. Only when it is plugged into the USB port, the flash drive will start, and the required power will be supplied by the USB connection. However, some flash drives (especially high-speed flash drives using the USB 2. standard) may need more power, so if they are connected to a USB hub built in a keyboard or screen, these flash drives will not work unless they are directly plugged into a controller (that is, a USB port provided by the computer itself) or an external USB hub. Graphics card-videocard, graphiccard and Video adapter: are one of the most basic components of personal computers. The purpose of the graphics card is to convert the display information needed by the computer system to drive the display, and provide the line scanning signal to the display to control the correct display of the display. It is an important component connecting the display with the motherboard of the personal computer and one of the important devices of "man-machine conversation". The graphics card is inserted into the expansion slot on the motherboard (now it is generally PCI-E slot, and there were AGP, PCI, ISA and other slots before). It is mainly responsible for converting the display signal sent by the host to the display into a general electrical signal, so that the display can understand what the personal computer is asking it to do. The main chip of the graphics card is called "Video chipset" (also called GPU or VPU, graphics processor or visual processor), which is the main processing unit of the graphics card. There is also a memory similar to computer memory on the graphics card, which is called "display memory" or "display memory". Hard disk-English: Hard Disk Drive (HDD for short) is a non-volatile storage device based on hard rotating disks used in computers. It stores and retrieves digital data on a flat magnetic surface. Information is written on the disk by electromagnetic current through the writing head close to the magnetic surface, and the polarity is changed by electromagnetic current. Information can be read back in the opposite way, for example, the magnetic field causes an electrical change in the coil or the reading head passes over it. Hard disks can be roughly divided into ATA(IDE) and SATA, SCSI and SAS according to different data interfaces. 5.25-inch and 3.5-inch desktop hard disks use D-shaped 4-pin power interface (commonly known as big 4pin), which is designed and patented by Molex Company. Or SATA power cord. The 2.5-inch hard disk for notebook computers can get power directly from the data port without additional power interface. After the external portable hard disk box is plugged in, the power supply is provided by the USB interface outside the computer, and the power supply of a single USB port is about 4~5V 5mA. If the power demand in mobile hard disk box is high, it is sometimes necessary to connect two USB ports to use it, otherwise, it needs external power supply. However, nowadays, most new hard disk boxes (using hard disks smaller than 2.5 inches) can easily use a single USB port to supply power. MotherMainboard-motherboard: it is the center or main circuit board that constitutes a complex electronic system, such as an electronic computer. A typical motherboard can provide a series of joints for processors, graphics cards, sound cards, hard disks, memories, external devices and other devices. They are usually inserted directly into the relevant slots or connected by wires. The most important component on the motherboard is the Chipset. Chipsets are usually composed of north bridge and south bridge, and some are designed with single chip to enhance their performance. These chipsets provide a common platform for the motherboard to connect different devices and control the communication between different devices. It also includes support for different expansion slots, such as processor, PCI, ISA, AGP, and PCI Express. Chipsets also provide additional functions for the motherboard, such as integrated video core and sound card (also known as built-in video core and built-in sound card). Some high-priced motherboards also integrate infrared communication technology, Bluetooth and 82.11(Wi-Fi) functions. ——Central Processing Unit (CPU) is one of the main equipment of electronic computer. Its function is mainly to interpret computer instructions and process data in computer software. That is, you can see the square thing plugged into the most square socket on the motherboard, but now that thing is mostly called a microprocessor, which is the main brain of the computer and executes a series of instructions stored in a program. When choosing Yes, you need to pay attention to whether the model matches the motherboard socket. Radiator: it is the thing that is added to the CPU. Of course, there are also hard disk radiators, graphics card radiators and memory radiators. Due to the continuous improvement of computer performance (the most direct thing is to improve power supply and work performance), considerable heat generation has become the most important problem to be solved, and then a radiator has emerged. The main function of the radiator is as its name suggests-radiating heat and reducing hardware temperature. Computer radiators can also be divided into active cooling and passive cooling. Active heat dissipation is to use fans or other power equipment to cool the main body of heat dissipation, generally including air cooling, water cooling and liquid cooling (the principle of air conditioning); Passive heat dissipation means that external equipment is not used for heat dissipation, and there are cooling towers in general. The above can also be called dynamic heat dissipation and static heat dissipation. Power supply: As the name implies, the equipment that provides energy source for our computer. There are many dense wires like octopus on the power supply to provide power supply for each equipment. Of course, it is necessary to connect the power cord before it can be powered on. Whether the power supply is sufficient directly affects the normal operation of the computer to some extent, so pay attention to whether the selection of power supply matches the overall configuration of the computer. Maybe some people are curious, isn't the power supply very big? In fact, the power supply is not large. The main body we see is the chassis, which is used to fix other computer hardware configured inside. The "square bag" where many wires protrude from the chassis is the power supply. When it comes to the chassis, the function is mainly fixed. Of course, it is getting smaller and smaller now (like Apple's mainframe), or it is integrated into the display. Network card-Network adapter or NIC (Network Interface Controller): It is a piece of computer hardware designed to allow computers to communicate on the computer network. Because it has a MAC address, it belongs to Layer 2 of the OSI model. It enables users to connect with each other by cable or wireless. Each network card has a unique 48-bit serial number called MAC address, which is written in a ROM on the card. Every computer on the network must have a unique MAC address. No two produced network cards have the same address. This is because the Institute of Electrical and Electronics Engineers (IEEE) is responsible for assigning unique MAC addresses to network interface controller vendors. The network card used to be plugged into the computer bus as an expansion card, but because of its low price and the widespread existence of Ethernet standards, most new computers have integrated network interfaces on the motherboard. These motherboards either integrate the function of Ethernet into the motherboard chip or use a cheap network card connected to the motherboard through PCI (or updated PCI-Express bus). Unless you need multiple interfaces or use other kinds of networks, you don't need a separate network card. Even newer motherboards may contain built-in dual network (Ethernet) interfaces. Sound card: it is an interface card used to process sound in multimedia computers. The sound card can convert the voice and music from the microphone, radio, tape recorder, CD player (laser disc) and other equipment into digital signals, and then hand them over to the computer for processing, and save them in the form of files. It can also restore the digital signals into real sound output. The interface at the rear of the sound card extends from the back of the chassis, and there are interfaces for connecting microphones, speakers, joysticks and MIDI devices. However, since All-In-One motherboards were promoted by major motherboard manufacturers, AC97 sound function has been built into motherboards. Forcing the low-end sound card market to shrink rapidly. Memory-computer memory is an electronic device made of semiconductor technology, which is used to store data. The data of electronic circuits are stored in binary form, and each storage unit of the memory is called a memory cell. Mouse: It is the hardware that we often operate the icon that it points on the display. It is a very common computer input device. It can locate the cursor on the current screen and operate the screen elements at the position where the cursor passes through through buttons, wheel devices or lasers. The ancestor of the mouse appeared in 1968. Douglas Englebart, an American scientist, made the first mouse in California. Keyboard: It is one of the peripherals of the computer, which is developed from the typewriter keyboard. You can input characters through the keyboard and control the operation of the computer. A computer keyboard consists of a rectangular or nearly rectangular group of buttons or "keys" with characters printed on them. In most cases, pressing a key will print a corresponding symbol, such as letters, numbers or punctuation marks. However, some special symbols need to be typed by pressing several keys at the same time or by pressing several keys in sequence. In addition, some keys do not correspond to any symbols, but affect the operation of the computer. Different input methods define different output symbols.