"The World is digital" reading notes

"The World is Digital" tells the knowledge of computers and the Internet that people in the mathematical age should know about. The book details how the so-called hardware, communication, programming, software, viruses, the Internet is how to form and associated.

In the first part of the hardware we learned that the first computer to actually implement the storage program was introduced in the UK in 1949, known as EDSAC (the English acronym for delayed storage of electronic automatic computers). The early computers used electronic tubes as basic computational elements. An electron tube is an electronic device of a size and shape similar to a cylindrical light bulb, with the disadvantage of being expensive, brittle, bulky, and cost-electric. With the invention of 1947 transistors and 1958 integrated circuits, the new era of computers really began. Equipment made with this technology is the reason why today's electronic systems are getting smaller, faster, and less expensive. A computer is a universal machine. It can be seen that the function of the computer is very powerful, all of which will eventually be reduced to bits. Anything that can be reduced to bits can be reproduced and processed by a digital computer.

The second part of the software, can let the computer complete a certain task sequence of instructions known as software. (1) algorithm. An algorithm is a series of precise, unambiguous steps that can perform a task and then stop. (2) complexity. The complexity of the algorithm is an abstract description of the amount of work to be performed by the algorithm. (3) programming. The algorithm is abstract, and the program is specific. (4) Programming language. A programming language is a library of tokens that express all of the computational steps that people can easily write out, and the code can be translated into a binary form that the computer can eventually execute.

The third part of communication, communication is in addition to hardware, software, the third pole. With communication, the computer can talk to the computer. Network bandwidth is a fundamental feature that describes the speed at which a system transmits data. The wait or delay measures the time required for a particular piece of information to pass through the system. Jitter, which is the variability of latency. It refers to the way in which a technology can be networked in a geographic context. Telephones with modems, the form of information transmitted by sound signals are called modulation. Instead, convert this form to a bit called demodulation. The device that can complete the modulation and demodulation functions is called a modem.

Finally, 1 for the hardware part, we understand the composition of the computer, how to represent and process information, and how the computer has changed over time. 2 software, for the professional students of our software engineering, we should know that the software is composed of computer data and instructions, different programming languages how to write programs, how the program becomes software. 3 The communication system is no far-off, ubiquitous. It is important to understand the flow of information, who can see it, and how the information is controlled.

This book tells us that no matter how changeable today's technology, people are unchanged. Let us learn more about the computer, by reading this book to let us know that we are not enough, let us more perfect ourselves, learn more new knowledge.

"The World is digital" reading notes