What is Linux & Why do we use it?
Linux came from a UNIX family. Linux is a free and open-source software operating system, which Linus Torvalds developed in September 1991. In 1991, Linus Torvalds was a student at the University of Helsinki, Finland, USA. He developed the first code of Linux 0.01 and posted it on the Minix newsgroup on 17 Sep 1991, his code became so popular that people encouraged him to develop new code and he was led to develop new code and release the first “official” version of Linux, version 0.02 on October 5, 1991.
Application: Software that performs specific tasks for the user within the operating system.
Kernel: The core component that manages system resources, hardware, and communication between software and hardware.
Shell: A command-line interface that allows users to interact with the operating system through commands.
“Today, many years pass and Linux has become one of the most popular operating systems. Today 90% of the fastest Supercomputers out of 500 run on Linux variants including the top 10.”
-——-Linux File System Hierarchy-———
In Linux, everything, including a hardware program, is represented as a file. The files are stored in a directory, and every directory contains a file with a tree structure. That is called the File System Hierarchy. Linux uses a single-root, inverted tree-like structure.
The root directory is represented by / (forward slash). It is a top-level directory in Linux.
| Directory | Uses |
| / | If someone says to look into the slash directory, they refer to the root directory |
| /root | It is the home directory for the root user (superuser). |
| /bin | Contains binary executable |
| /sbin | The Linux commands located under this directory are used typically by the system administrator for system maintenance purposes |
| /dev | It contains hardware device files. |
| /var | The variable data files, such as log file,s are located in the /var directory |
| /mnt | This directory is used to mount a file system temporarily |
| /media | This directory contains sub-directories where removable media devices inserted into the computer are mounted |
| /usr | This directory contains applications and files used by users, as opposed to applications and files used by the system |
| /etc | It contains all the configuration files of the server |
| /boot | This directory contains the files needed to boot the system |
| /opt | This directory is used for installing the application software from third-party vendors that are not available in the Linux distribution |
| /home | It contains the secondary users’ home directory |
| /tmp | Directory that contains temporary files created by the system and users |
