Posts Tagged ‘Linux’
Introduction to Linux
Posted by: capturdivya on: May 24, 2011
Operating System:
- An operating system is composed of two major parts; these parts are known as the “kernel” and the “userland“.
- The kernel is responsible for handling communication between the physical hardware and the software running on the machine.
- The “userland” is comprised of system utilities and user applications. These include editors, compilers and server daemons.
- System utilities allowing you to maintain,monitor and even upgrade your system are also included.
Linux-Free and open source OS
- In the Linux operating system,Linux is a kernel, and requires additional software in order to make it an operating system.
- A Linux distribution is comprised of the Linux kernel, and a collection of “userland” software.
- The software is usually provided by the FSF23 and GNU24 organisations,as well as many private individuals. Some of it even originates from UCB’s25 BSD26 Unix operating system
Components of the OS:
1.Hardware
This is the physical equipment of the computer is composed.It includes
- keyboard and mouse
- video card and monitor
- network card
- CPU and the RAM
Kernel
- The Linux kernel acts as the interface between the hardware and the rest of the operating system.
- The Linux kernel also contains device drivers, which are specific to the hardware peripherals
- The kernel is also responsible for handling things such as the allocation of resources(memory and CPU time), as well as keeping track of which applications are busy with which files, as well as security; and what each user is allowed to do on the operating system.
Standard Library of Procedures
- A Linux based operating system will have a standard library of procedures, which allows the “userland” software to communicate with the kernel.
- On most Linux based operating systems, this library is often called “libc”.
Examples
calls to ask the kernel to open up a file for reading or writing, or to display text on the display,
even read in keystrokes from the keyboard.
Standard Utilities and User Applications
- A Linux based system will usually come with a set of standard Unix-like utilities; these are usually simple commands that are used in day-to-day use of the operating system, as well as specific user applications and services.
- This is typically software that the GNU Project has written and published under their open source license, so that the software is available for everyone to freely copy, modify and redistribute.
Example Commands, which allow users to edit and manipulate files and directories, perform calculations and even do jobs like the backups of their
data