Translations of this material:

into Portugese: Translation of "OPERATING SYSTEMS: HIDDEN SOFTWARE". Translation is not started yet.
Submitted for translation by maximo 09.10.2018
into Spanish: OPERATING SYSTEMS: HIDDEN SOFTWARE. 2% translated in draft.
Submitted for translation by alecastillo 06.04.2018
into English: Операционные системы. Спрятанное ПО. Translated in draft, editing and proof-reading required.
Submitted for translation by saturn4er 15.05.2016


When a brand new computer comes off the factory assembly line, it can do nothing. The hardware needs software to make it work. Are we talking about applications software such as wordprocessing or spreadsheet software? Partly. But an applications software package does not communicate directly with the hardware. Between the applications software and the hardware is a software interface - an operating system. An operating system is a set of programs that lies between applications software and the computer hardware.

The most important program in the operating system, the program that manages the operating system, is the supervisor program, most of which remains in memory and is thus referred to as resident. The supervisor controls the entire operating system and loads into memory of other operating system programs (called nonresident) from disk storage only as needed.

An operating system has three main functions: manage the computer's resources, such as the central processing unit, memory, disk drives, and printers, establish a user interface, and execute and provide services for applications software. Keep in mind, however, that much of the work of an operating system is hidden from the user. In particular, the first listed function, managing the computer's resources, is taken care of without the user being aware of the details. Furthermore, all input and output operations, although invoked by an applications program, are actually carried out by the operating system.