History of Linux:
Linux came from unix family , linux is open source software which was originally built by Linux Torvald who was the student of University of Helsinki, Finland in 1991.
Today Linux is one of the most popular operating system and 90% fastest Supercomputers out of 500 run on linux variant.
Linux File System Hierarchy
Everything in linux is represented as file or directory including the linux operating system iteself is stored in file as well as hardware. Every directory contains a file with tree structure which is also known as File System Hierarchy.
Variations of Linux
There are various types of variations in linux used for different purposes such as Kali linux which is mostly used for ethical hacking purpose. Some of the variation of linux are as follows:
Ubuntu
CentOS
RedHat
AmazonLinux2(AL2)
Fedora
Kali-Linux
parrot
Debian
Arch
SUSE
The Linux Architecture
The linux architecture is very clear and simple, it has 4 levels which can be classified as
Hardware: The inner circle describes Hardware which is the main component of linux architecture where ultimately our commands go and file storage location resides in hardware. The new file made take its storage memory from hardware.
Kernel: It is the heart of an operating system, which allocates time and memory to program, handles communication and file storage.
Shell: It can be described as the interface between user and kernel. It is the part of OS where we deploy commands to get response from OS.
Application: The computer operating system interface to the hardware or it is mainly the GUI part where we can give command to hardware through graphical user interface without use of shell commands is called Application.
Some detailed Commands:
cd / This command "/" is root when entered , this will make your file location to start at root location where the linux operating system is present. This location will have all the file and directories related to operating system.
cd /bin After going to this directory , you can see a bunch of files and directories which is mainly the commands you are going to use. The total of basic user commands sum up to approximately 800. This files are mostly made up of binary code which are also known as binary executable files.
cd /sbin This sbin folder is also known as System Binary Executable files , this folder are mainly used by system administrator or for system maintenance purpose.
These folder contains the file or command such as ifconfig, reboot, fdisk, swapon etc.
lsb_release -a This command is the give information about the version of Operatins sytem you are using. Take an example: ubuntu 22.04.3 LTS.
Here LTS stands for long term support version. These type of version are for long term as it does not have frequent updates. 22 is the year which is 2022 and 04 is month of April . The linux operatins sytem release their updates twice in year which is mainly in April and September.
Some basic linux Commands
