Basics of Linux

Linux is a free Unix-like operating system.

• Linux is an implementation of UNIX.

• The Linux operating system is written in the C programming language.

• Linux uses GNU tools, a set of freely available standard tools for handling the operating system.

In Linux everything is a file.To organize our files into a system we use folders. The lowest possible folder is root / where you will find the user homes called /home/.

  /   /home/   /home/mom/   /home/dad/

Every file belongs to a user and a group. Linux has one special user called root . Root is the "system administrator" and has access to all files and folders. This special user has the right to do anything.

To run Linux commands, you need to get to the Linux command line prompt.To get to the Linux command line prompt from a Linux desktop, you open a terminal emulation window.When you open a terminal emulation window, you get a "window" on the desktop.This window shows the Linux command line prompt, at which you can run Linux commands . After running a Linux command, this window also shows the output of the command.

Linux commands

• mkdir -make directories
• cd - change directory
• mv - move (rename) files
• pwd - print name of current/working directory
• ls - list directory contents
• rm - remove files or directories
• chmod -change file access permissions

syntax: chmod [-r] permissions file name

r Change the permission on files that are in the subdirectories of the directory that you are currently in.permission Specifies the rights that are being granted. Below is the different rights that you can grant in an alpha numeric format.filenames File or directory that you are associating the rights with Permissions

u - User who owns the file.

g - Group that owns the file.

o - Other.

a - All.

r - Read the file.

w - Write or edit the file.

x - Execute or run the file as a program.

• mount - mount a file system
• cp - copy files and directories
• vim - Vi IMproved, a programmers text editor