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INFORMATION, MACHINE WORDS, INSTRUCTIONS, ADDRESSES AND REASONABLE OPERATIONS
1. Information is a set of marks or signs that have meaning. These consist of letters or numbers, digits or characters, typewriter signs, other kinds of signs, and so on. A computer reacts differently to different digits or characters, and reacts to them as units that have meaning. For example, information for an analog computer has to be in the form of distances, or rotations, or voltages, or other physical variables. And for a digital computer information has to be in the form of digits or numbers.
2. Any information may be represented by the binary system including two digits: one (1) and zero (0). Each I and 0 is a separate binary digit called a bit. A bit is the smallest part of information. Bits are typically grouped in units that are called bytes. A byte is the basic unit of information used in modern computers and consists of eight bits.
3. The bytes are handled usually in standard groups called machine words or just words. There are two basic types of information or words that can be put into a memory cell or location, words that are numerical quantities and words that are computer instructions. Regularly, an instruction to the machine is expressed as a word; and so the same set of characters may have meaning sometimes as a number, sometimes as an instruction. A speed of 96,000 characters per second is the same as a speed of 8,000 words per second. Most human beings could not take even 12-digit number per second.2
4. Physically the set of bits is a set of arrangements of some physical equipment. One of the ways of storing information in a computer is storing by using a set of small magnetically polarized spots on a magnetic surface.
5. The computer is told what operations to perform by means of instructions. An instruction is a command to the computer. It consists of a verb (an operational code) and a noun (an operand). For example, if the computer is instructed "Add 365 the number of times stated in the register R", and if the register R stores the code for number 3, then the computer will perform that operation three times. An instruction word looks like a number, and there is no way to tell from the word itself whether it is a quantity or an instruction. The computer must be told exactly which address contains an instruction and which contains a quantity.
6. An address is the name of particular memory location or cell. Each memory location (word or byte) has its own unique address or number just like a post office box.3 For example, if the computer contains 100 memory cells, their respective addresses might be the numbers 4 from 1 to 100 (or 0 through 99). And instead of saying "A word is in a memory cell", the computer personnel say, "The contents of an address is a word."
7. Reasonable operations are mathematical and logical. Mathematical operations include arithmetic and algebraic operations. Arithmetic operations are addition, subtraction, multiplication, division, taking a square root, etc.; and algebraic operations are called raising to a power as well as differentiating and integrating.
8. Logical operations include comparing, selecting, sorting, matching, etc. These are operations which may be performed either on numbers, or on expressions consisted of letters such as ordinary words. A very important logical operation performed by a computer is determining, i.e., which of two operations is to be performed next.
ИНФОРМАЦИЯ, МАШИННЫЕ СЛОВА, КОМАНДЫ, АДРЕСА И РАЦИОНАЛЬНЫЕ ОПЕРАЦИИ
II.
1. Information is a set of marks or signs that have meaning.
Реферат:
The headline of the article is "INFORMATION, MACHINE WORDS, INSTRUCTIONS, ADDRESSES AND REASONABLE OPERATIONS".
The article is devoted to the description of the principal terms of computer science: information, machine words, instructions, addresses and reasonable operations.
The purpose of the article is to give the reader some information on the operations the computer performs with the numbers and digits.
The author starts by giving the definition of the information itself.
He continues by telling the readers about the way information can be represented by the binary system, defining the terms "bit" and "byte". The latter is the basic unit of information, used in modern computers and consists of eight bits.
Furthermore, the author dwells upon the two types of machine word, which can be either numerical quantities or computer instructions.
Moreover, he describes the ways of storing information in a computer by using a set of magnetically polarized spots on a magnetic surface.
The author states that an instruction is a command to the computer and that it consists of a verb and a noun. He thinks that there is no way to tell from the word itself if it is a quantity or an instruction. The article also describes the function of memory locations.
In conclusion the article reads about the types of reasonable operators. They are divided into mathematical (addition, division, multiplication, raising to power etc.) and logical (selecting, sorting, matching etc.).
I found the article cognitive and very important, because it throws some light upon the functioning of computer language and introduces the reader to the basic terms of informatics.
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