In the history of computing, we can trace the development of two main areas of its use. The first field is application of computational technique for performing numerical calculations, which take too long or are impossible to perform manually. Development of this sphere promoted intensification of methods of numerical solution of complex mathematical tasks, appearance of programming languages, oriented on convenient record of numerical algorithms, formation of feedback with developers of new computer architectures. A characteristic feature of this field of computer technology application is the presence of complex processing algorithms, which are applied to data simple in structure and which volume is comparatively small.
The second area, which directly relates to our topic, is the use of computers in automatic or automated information systems. An information system is a hardware and software system that provides the following functions:
reliable storage of information in computer memory;
performance of application-specific information transformations and calculations;
Providing users with a convenient and easily mastered interface.
Usually such systems deal with large volumes of information with a rather complex structure. Classic examples of information systems are banking systems, automated enterprise management systems, reservation systems for air or train tickets, hotel rooms, etc. In the meantime you can plat casinos here online casino real money nz.
The second area of computer technology use emerged somewhat later than the first. This is connected with the fact that in the beginning of computer technology the ability of computers to store information was very limited. We can speak about safe and long-lasting information storage only if there are memory devices that keep information after turning off the electric power. The main memory of computers usually doesn’t have this feature. The first computers used two kinds of external memory devices – magnetic tapes and drums. Magnetic tapes had a rather large capacity, but their physical nature provided sequential access to data. Magnetic drums (they are closest to modern magnetic disks with fixed heads) allowed random access to data, but had a limited amount of stored information.
These limitations were not too significant for purely numerical calculations. Even if a program has to process (or produce) a large amount of information, it is possible in programming to think about the arrangement of this information in external memory (e.g., on sequential magnetic tape) to ensure efficient execution of that program. However, in information systems, a set of interrelated information objects actually reflects a model of real world objects. And the users’ need for information adequately reflecting the state of real-world objects requires a relatively quick reaction of the system to their requests. And in this case, the availability of relatively slow data storage devices, which include magnetic tapes and drums, was insufficient.Minimum deposit casinos are here.
We can assume that it was the requirements of nonnumerical applications that caused the appearance of removable magnetic disks with movable heads, which was a revolution in the history of computing. These external memory devices had significantly greater capacity than magnetic drums, provided satisfactory data access speed in random sampling mode, and the ability to change the disk packet on the device allowed for a virtually unlimited data archive.
With the advent of magnetic disks began the history of external memory data management systems. Prior to that, each application program that needed to store data in external memory determined by itself the location of each data portion on a magnetic tape or drum, and performed exchanges between main memory and external memory devices using low-level hardware and software (machine commands or calls to the corresponding operating system programs). This mode of operation does not allow or makes it very difficult to maintain multiple archives of permanently stored information on a single external medium. In addition, each application program had to solve the problems of naming data parts and structuring data in external memory.
