In recent decades, humanity has entered the computer age. Smart and powerful computers, based on the principles of mathematical operations, work with information, manage the activities of individual machines and entire factories, control the quality of products and various products. In our time, computer technology is the basis for the development of human civilization. On the way to this position, a short but very turbulent path had to be passed. And for a long time these machines were called not computers, but computers (computers).
Computer classification
According to the general classification, computers are distributed over a number of generations. The determining properties when classifying devices to a particular generation are their individual structures and modifications, such requirements for electronic computers as speed, memory size, control methods and data processing methods.
Of coursethe distribution of computers will in any case be conditional - there are a large number of machines that, according to some signs, are considered models of one generation, and according to others, belong to a completely different one.
As a result, these devices can be classified as non-coinciding stages of the formation of models of an electronic computing type.
In any case, the improvement of computers goes through a series of stages. And the generation of computers of each stage has significant differences from each other in terms of elemental and technical bases, certain support of a particular mathematical type.
The first generation of computers
Generation 1 computing machines developed in the early post-war years. Not very powerful electronic computers were created, based on electronic type lamps (the same as in all TV models of those years). To some extent, this was the stage of formation of such a technique.
The first computers were considered experimental types of devices that were formed to analyze existing and new concepts (in various sciences and in some complex industries). The volume and mass of computer machines, which were quite large, often required very large rooms. Now it seems like a fairy tale of long gone and even not quite real years.
The introduction of data into the machines of the first generation went by the method of loading punched cards, and the program management of the sequences of solving functions was carried out, for example, in ENIAC - by the method of entering plugs and forms of a typesetting sphere.
Despiteto the fact that such a programming method took a lot of time in order to prepare the unit, for connections on the typesetting fields of machine blocks, it provided all the opportunities to demonstrate the mathematical "abilities" of ENIAC, and with significant benefits it had differences from the program punched tape method, which is suitable for relay type machines.
The principle of "thinking"
Employees who worked on the first computers did not leave, they were constantly near the machines and monitored the efficiency of the existing vacuum tubes. But as soon as at least one lamp failed, ENIAC instantly rose, everyone in a hurry searched for the broken lamp.
The leading reason (albeit approximate) for the very frequent replacement of lamps was the following: the heating and radiance of the lamps attracted insects, they flew into the internal volume of the apparatus and “helped” create a short electrical circuit. That is, the first generation of these machines was very vulnerable to external influences.
If we imagine that these assumptions could be true, then the concept of "bugs" ("bugs"), which means errors and blunders in software and hardware computer equipment, has a completely different meaning.
Well, if the car's lamps were in working order, maintenance personnel could tune the ENIAC for another task by manually rearranging the connections of about six thousand wires. All these contacts had to be switched again when a different type of task arose.
Serial machines
The first electronic computer, which began to be mass-produced, was UNIVAC. It became the first kind of multi-purpose electronic digital computer. UNIVAC, which dates back to 1946-1951, required an addition period of 120 µs, total multiplications of 1800 µs, and divisions of 3600 µs.
Such machines required a large area, a lot of electricity and had a significant number of electronic lamps.
In particular, the Soviet electronic computer "Strela" had 6400 of these lamps and 60 thousand copies of semiconductor type diodes. The speed of this generation of computers was not higher than two or three thousand operations per second, the size of the RAM was no more than two Kb. Only the M-2 unit (1958) reached the RAM of about four KB, and the speed of the machine reached twenty thousand actions per second.
second generation computers
In 1948, the first working transistor was obtained by several Western scientists and inventors. It was a point-contact mechanism in which three thin metal wires were in contact with a strip of polycrystalline material. Consequently, the family of computers improved already in those years.
The first models of transistorized computers released date back to the last half of the 1950s, and five years later external forms of the digital computer appeared with greatly enhanced functions.
Architecture Features
One ofThe important principle of the transistor is that in a single copy it will be able to do some work for 40 ordinary lamps, and even then it will maintain a higher speed of operation. The machine emits a minimal amount of heat, and will hardly use electrical sources and energy. In this regard, the requirements for personal electronic computers have grown.
In parallel with the gradual replacement of conventional electric-type lamps with efficient transistors, there has been an increase in the improvement of the technique for storing available data. Memory expansion is underway, and magnetic modified tape, which was first used in the first generation of UNIVAC computers, has begun to improve.
It should be noted that in the mid-sixties of the last century, the method of storing data on disks was used. Significant advances in the use of computers made it possible to obtain a speed of a million operations per second! In particular, "Stretch" (Great Britain), "Atlas" (USA) can be reckoned among ordinary transistor computers of the second generation of electronic computers. At that time, the USSR also produced high-quality computer models (in particular, BESM-6).
The release of computers based on transistors caused a reduction in their volume, weight, electricity costs and the cost of machines, as well as improved reliability and efficiency. This made it possible to increase the number of users and the list of tasks to be solved. Taking into account the features that distinguished the second generation of computers,the developers of such machines began to construct algorithmic forms of languages for engineering (in particular, ALGOL, FORTRAN) and economic (in particular, COBOL) types of calculations.
Hygienic requirements for electronic computers are also increasing. In the fifties there was another breakthrough, but still it was still far from the modern level.
Importance of OS
But even at that time, the leading task of computer technology was to reduce resources - working time and memory. To solve this problem, they then began to design prototypes of current operating systems.
The types of the first operating systems (OS) made it possible to improve the automation of the work of computer users, which was aimed at performing certain tasks: entering program data into the machine, calling the necessary translators, calling the modern library subroutines necessary for the program, etc.
Therefore, in addition to the program and various information, in the second generation computers it was necessary to leave also a special instruction, where the processing steps and a list of data about the program and its developers were indicated. After that, a certain number of tasks for operators (sets with tasks) began to be introduced into machines in parallel, in these forms of operating systems it was necessary to divide the types of computer resources between certain forms of tasks - a multiprogramming method of working for studying data appeared.
Third Generation
Due to developmentThe technology of creating integrated circuits (ICs) of computers managed to obtain an acceleration of the speed and degree of reliability of existing semiconductor circuits, as well as another reduction in their dimensions, the amount of power used and the price.
Integrated forms of microcircuits now began to be made from a fixed set of electronic type parts, which were supplied in rectangular elongated silicon wafers, and had a length of one side no more than 1 cm. This type of wafer (crystals) is placed in a plastic case of small volumes, dimensions in it can only be calculated using the selection of the so-called. "legs".
Because of these reasons, the pace of development of computers began to rapidly increase. This made it possible not only to improve the quality of work and reduce the cost of such machines, but also to form devices of a small, simple, inexpensive and reliable mass type - a minicomputer. These machines were originally designed to solve highly technical problems in various exercises and techniques.
The leading moment in those years was considered the possibility of unifying machines. The third generation of computers is created taking into account compatible individual models of different types. All other accelerations in the development of mathematical and various software contribute to the formation of batch programs for the solvability of standard problems of a problem-oriented programming language. Then, for the first time, software packages appear - forms of operating systems on which the third generation of computers develops.
Fourth Generation
Active improvement of electronic devices of computerscontributed to the emergence of large integrated circuits (LSI), where each crystal contained several thousand electrical-type parts. Thanks to this, the next generations of computers began to be produced, the elemental basis of which received a larger amount of memory and reduced cycles for the implementation of commands: the use of memory bytes in one machine operation began to decrease significantly. But, since programming costs have hardly decreased, the tasks of reducing resources of a purely human type, and not of a machine type, as before, have come to the fore.
Operating systems of the next types were produced, which enabled operators to improve their programs directly behind the computer displays, this simplified the work of users, as a result of which the first developments of a new software base appeared soon. This method absolutely contradicted the theory of the initial stages of information development, which used computers of the first generation. Now computers began to be used not only for recording large amounts of information, but also for automation and mechanization of various fields of activity.
Changes in the early seventies
In 1971, a large integrated circuit of computers was released, where the entire processor of a computer of conventional architectures was located. It has now become possible to arrange in one large integrated circuit almost all electronic type circuits that were not complex in a typical computer architecture. Thus, the possibilities of mass production of conventional devices for smallprices. This was the new, fourth generation of computers.
Since that time, a lot of inexpensive (used in compact keyboard computers) and control circuits have been produced that fit on one or several large integrated circuit boards with processors, sufficient RAM and a structure of connections with executive-type sensors in control mechanisms.
Programs that worked with the regulation of gasoline in car engines, with the transfer of certain electronic information or with fixed washing modes, were introduced into computer memory or using various types of controllers, or directly at enterprises.
The seventies saw the beginning of the production of universal computing systems that combined a processor, a large amount of memory, circuits of various interfaces with an input-output mechanism located in a common large integrated circuit (the so-called single-chip computers) or, in other versions, large integrated circuits located on a common printed circuit board. As a result, when the fourth generation of computers became widespread, a repetition of the situation that had developed in the sixties began, when modest minicomputers performed part of the work in large mainframe computers.
Fourth-generation computer properties
The fourth generation electronic computers were complex and had branched capabilities:
- normal multiprocessor mode;
- programs of a parallel-sequential type;
- high-level types of computer languages;
- emergencefirst computer networks.
The development of the technical capabilities of these devices was marked by the following provisions:
- Typical signal delay by 0.7 ns/v.
- The leading type of memory is a typical semiconductor. The period of generation of information from this type of memory is 100–150 ns. Memory - 1012-1013 characters.
Using hardware implementation of operating systems
Modular systems have begun to be used for software-type tools.
The first personal electronic computer was created in the spring of 1976. Based on the integrated 8-bit controllers of a conventional electronic game circuit, scientists produced a conventional BASIC-programmed Apple game machine, which gained great popularity. In early 1977, Apple Comp. appeared, and the production of the first Apple personal computers on Earth began. The history of this computer level highlights this event as the most important.
Today, Apple manufactures Macintosh personal computers, which in many respects surpass the IBM PC models. Apple's new models are distinguished not only by exceptional quality, but also by extensive (by modern standards) capabilities. A special operating system has also been developed for computers from Apple, which takes into account all their exceptional features.
The fifth generation of computers
In the eighties the process of development of computers (computer generations) enters a new stage - fifth generation machines. The appearance of these devicesassociated with the development of microprocessors. From the standpoint of system constructions, absolute decentralization of work is characteristic, and considering software and mathematical bases, movement to the level of work in the program structure is characteristic. The organization of the work of electronic computers is growing.
The efficiency of the fifth generation of computers is one hundred eight to one hundred and nine operations per second. This type of machine is characterized by a multiprocessor system, which is based on microprocessors of weakened types, which are used immediately in the plural. Now there are electronic computing types of machines that are aimed at high-level types of computer languages.
