Computers usually consist of the following devices:

The central processing unit ( CPU, Central Processing Unit)
There aren’t many people who call it a “central processing unit” in Japanese. CPU is normal. A device that processes data.

The main storage device ( Main Memory )
A device that stores data. It is used to memorize the program being executed and to store the data necessary for the program to work. This is also katakana and is often called main memory.

The auxiliary storage device (auxiliary memory)
A device that stores data. Operating speed is slower than main memory. The usual usage is to store data permanently. Files are usually saved here. I don’t say “auxiliary memory” in katakana because it’s difficult to pronounce.

The input device (input device)
A device for giving data and instructions to a computer.

Output device (output device)
A device for retrieving data from a computer and displaying processing results.

Inputs and outputs are often referred to as input/output, and the term input/output device is often used to combine input devices and output devices. Input/output is shortly called I / O in English (a word that comes from Input / Output). There are often devices that double as input devices and output devices. The main storage device and various auxiliary storage devices are collectively called storage devices. The main memory device, current, silicon (silicon, elemental symbols Si, a typical semiconductor such) a is produced as the main raw material a semiconductor memory which is called an (especially RAM to use a what is called) Average. More on that later. Auxiliary storage devices include hard disks and floppy disks. This will be explained in detail later. A typical example of an input device is a keyboard and a mouse. Typical examples of output devices include displays (various types) and printers. There are other devices for communicating with other computers, but this can also be seen as a type of input/output device. (It is not the human being who inputs and receives the data, but the computer to which it is connected.) However, the communication device may be considered independently.

Five major computers
Previously-mentioned CPU, storage device, input device, in addition to an output device may as a component of a computer control device, but is listed in the figure above, the control device is contained within the CPU and each interface It does not appear on the surface because it is present. In addition, there is a document that includes an arithmetic unit as a component, but it is contained in the CPU and executes four arithmetic operations and logical operations. Since some parts of the CPU are in control, it can be roughly considered that the CPU is made up of a control unit and an arithmetic unit. Often, they are classified into five categories: control devices, arithmetic devices, storage devices, input devices, and output devices, and these are called the five major devices of calculators.

ROM
ROM is a word derived from Read-Only Memory and is read as “ROM”. A ROM is a storage element that can read the data recorded in it but cannot write new data (rewrite the written data) to it. (I’ll see later on what to use it for.) Then, when to put the contents, the data is written at the time of manufacturing the ROM. The stored contents of the ROM are not erased even when the power is turned off.

RAM
RAM is a word derived from Random Access Memory and is read as “ram”. RAM usually occupies most of the main memory. It has the feature of ” random access ” and the feature of ” reading and writing at any time “.

A little IC story
In the old days, the only way to build an electronic circuit was to connect many parts with wires. The cost was very high as the number of parts increased. However, the semiconductor thin piece ( chip ( Chip numerous to hereinafter)) device method of incorporating is an invention, the situation was completely changed. A circuit made in this way is called an integrated circuit ( IC ). (Elements: basic electronic components, resistors, capacitors, transistors, etc.) Semiconductors have properties intermediate between conductors and insulators. That is, it is not as easy to conduct electricity as a conductor such as metal, but it is not an insulator. Silicon (silicon, element symbol is Si ) is usually used as a semiconductor material. You also need a sharpener like knivsliper to sharpen your tools.