The Book of the World is digital

We live in an age surrounded by numbers. Information changes rapidly, open the computer can see a lot of news, not only the country and other countries. These rely on the internet to spread so quickly, and the Internet relies on computers to show people. The world's first computer Eniac was born in 1964 at the University of Pennsylvania in the United States, its volume is very high, power consumption, can store less data, the CPU can not do very advanced calculation. However, the development of the computer now more and more like the volume of the CPU faster and faster, can store more and more data. A 2.1GHz processor that Beats 2.1 billion times per second. The human heartbeat is about 1 Hertz, which is about 100,000 times a day, nearly 30 million times a year, so the human heart beats for 70 years to catch the CPU's beating in a second. Now the computers are all digital computers. All of this ends up being a bit, a single or group representation of information in digital form, so-called information may be instructions or data. The computer uses binary to represent data, why not use decimal? That's why people can understand it because high and low levels are not ideal for rectangular waves, only 1 and 0 are stable by high and low levels. 10, the current circuit is not able to accurately quantify, and the level is not ideal high and low jump change. The first use of the tube, with paper tape punch record data. Now the basic Integrated Circuit sub-TTL and CMOS two kinds. The most basic gate circuit is the inverter, which is the conversion between the high and low levels. The TTL gate circuit is the transistor composition. The CMOS inverter consists of an n-channel transistor and a P-channel transistor. The current CPU is using a FET. The 74 series IC produced by German instrument is the standard and template of digital circuit. Now the hard drive capacity is growing, a computer can put a whole library of books in the computer.

No matter how much hardware, the computer must have software to enrich themselves. The hardware of a computer is controlled by software. Hardware-only computers are called bare metal. According to the degree of hardware-related, the computer software is usually divided into system software and application software. The software that the user uses directly is usually the application software, and the application software usually directs the computer hardware to complete its function through the system software. The most important system software is the operating system (Operation System,os), which completes the various details of directing the computer's operation, that is, the operating system is used to command and manage its own software in the computer system. In essence, when using a computer, we do not directly use the computer's hardware, and we deal directly with the application software. We use the application software, the application software in the "Behind the scenes" with the operating system, and then by the operating system to command the computer to do the corresponding work.

Software needs to be written in programming programs, a common software may include hundreds of thousands of of the code, software is not just a person to write, usually by a team to work together to write each other.

In our "Three pillars" world, communication is the third pole in addition to hardware and software. In any case, communication is what really makes everything interesting. With the communication between computers to communicate with each other, and this communication is for us to provide convenience. The web was born in the middle of the 1990, and it turned the internet of few people into a daily necessity for every one of us.

The network transforms the information into physical representations so that it can be transmitted through some medium, and at the point of transmission, they convert these physical forms back into a form that people understand. The network is also divided into LAN and Ethernet, and now has the most fire wireless network.

The Book of the World is digital