A program is a description, in a formal language “understandable” to a computer, of a sequence of actions to be performed on data to solve a given problem.

All programs designed to run on a computer are called computer software.

Without software, a computer cannot work. Therefore, we consider the computer as a system – a single unit consisting of interrelated parts: hardware and software.

The scope of a particular computer is determined by both its technical means and the software installed.

The software of modern computers has a huge number of programs, it continually evolves – existing programs are improved, some programs are replaced by others, there are new programs.

The variety of computer software can be divided into three groups: system software, application software, programming systems.

System software includes operating system and service programs.

The operating system is a set of programs that provide the joint functioning of all computer devices and gives the user access to computer resources.

The operating system includes programs that support the dialogue between the user and the computer: wanting to perform some action, the person gives the OS the appropriate command.

The computer is a part of the “human-computer” system.

The means that provide the relationship between objects in this system, called an interface.

Nowadays computers are sold both without an OS and with an operating system already installed. Another operating system can be installed on the computer if the user wishes. When an operating system is installed, the programs that are part of it are copied to the computer’s hard drive. The programs of the operating system are stored in non-volatile memory on the hard disk after the installation.

Booting Your Computer

Booting the computer is the sequential loading of the operating system programs from the non-volatile memory (hard disk or optical disc) into the computer’s RAM.

Service programs

Archivers are special programs that compress programs and data. Archiving programs provide a reduction in the size of the stored information and, therefore, saves disk space and reduces the copying time of this information, which is especially important when forwarding information over the Internet.

A computer virus is a specially written malicious program that can damage data on your computer or disable it. To detect and remove computer viruses, as well as to protect against them experts develop anti-virus programs.

In order not to expose your computer to viruses and to ensure reliable data storage, it is necessary to follow the rules:

1) Install an antivirus program on your computer and regularly test your computer for viruses with it;

2) Regularly update your antivirus program via the Internet;

3) Before reading information from random media check for viruses.

Communication programs – designed to provide access to Internet resources and communication between users.