What is an Operating System?
An operating system is the main program of a computer that allows the execution of every other program. It manages:
Input from the keyboard and other devices
Output to the monitor, printer, and peripheral devices
Organization of files and directories
Control of computer resources
Historically, the first well-known system was IBM’s DOS in 1981. Microsoft later introduced Windows 3.11, a simpler and more user-friendly system for the general public. Later came the well-known versions: Windows 95, NT, 98, ME, 2000, XP, Vista, 7, 8, etc.
There are also other operating systems, such as UNIX and Linux, which are mostly used on servers and professional environments.
Purpose of an Operating System
An operating system has several key functions:
Manages computer resources (CPU, RAM, HDD, GPU)
Facilitates communication between the user and the computer
Provides an environment for program execution
Manages processes, files, and resources
Operation of an Operating System
Process Control
A process is a unit of work. The operating system manages processes by:
Creating or terminating processes
Handling asynchronous events and signals
Creating and managing different threads
File System
The file system organizes files and directories. For example:
/– system root/dev– physical devices/proc– information about processes
Commands like cd, ls, stat, link, or unlink allow users to navigate and manage files and directories.
Main Activities of an Operating System
Manages mass memory (HDD) and RAM
Manages processes (CPU)
Provides simultaneous multi-user access
Manages the graphical interface (GPU)
Allows simultaneous execution of multiple processes
