Linux is a free, open-source operating system, released under the GNU General Public License (GPL). Anyone can run, study, modify, and redistribute the source code, or even sell copies of their modified code, as long as they do so under the same license.
Linux operating system
An operating system can be described as an interface between the computer hardware and the user of any computer. It is a group of software that handles the resources of the computer hardware and facilitates basic services for computer programs. An operating system is an essential component of system software within a computer system. The primary aim of an operating system is to provide a platform where a user can run any program conveniently or efficiently.
On the other hand, Linux OS is one of the famous versions of the UNIX OS. It is developed to provide a low-cost or free OS for several personal computer system users. Remarkably, it is a complete OS Including an X Window System, Emacs editor, IP/TCP, GUI (graphical user interface), etc.
The architecture of the Linux system
The Linux operating system's architecture mainly contains some of the components: the Kernel, System Library, Hardware layer, System, and Shell utility.
1. Kernel:- The kernel is one of the core sections of an operating system. It is responsible for each of the major actions of the Linux OS. This operating system contains distinct types of modules and cooperates with underlying hardware directly. The kernel facilitates the required abstraction for hiding details of low-level hardware or application programs in the system. There are some of the important kernel types are mentioned below:
Monolithic Kernel
Microkernels
Exo kernels
Hybrid kernels
2. System Libraries:- These libraries can be specified as some special functions. These are applied for implementing the operating system's functionality and don't need code access rights for the modules of the kernel.
3. System Utility Programs:- It is responsible for doing specialized level and individual activities.
4. Hardware layer:- Linux operating system contains a hardware layer that consists of several peripheral devices like CPU, HDD, and RAM.
5. Shell:- It is an interface between the kernel and the user. It can afford the services of kernel. It can take commands through the user and runs the functions of the kernel. The shell is available in distinct types of OSes. These operating systems are categorized into two different types, which are graphical shells and command-line shells.
The graphical line shells facilitate the graphical user interface, while the command line shells facilitate the command line interface. Thus, both of these shells implement operations. However, the graphical user interface shells work slower as compared to the command-line interface shells.
Linux Operating System Features
Some of the primary features of Linux OS are as follows:
Portable: Linux OS can perform different types of hardware and the kernel of Linux supports the installation of any type of hardware environment.
Open source: Linux operating system source code is available freely and for enhancing the capability of the Linux OS, several teams are performing in collaboration.
Multiprogramming: Linux OS can be defined as a multiprogramming system. It means more than one application can be executed at the same time.
Multi-user: Linux OS can also be defined as a multi-user system. It means more than one user can use the resources of the system such as application programs, memory, or RAM at the same time.
Hierarchical file system: Linux OS affords a typical file structure where user files or system files are arranged.
Security: Linux OS facilitates user security systems with the help of various features of authentication such as controlled access to specific files, password protection, or data encryption.
Shell: Linux operating system facilitates a unique interpreter program. This type of program can be applied for executing commands of the operating system. It can be applied to perform various types of tasks such as call application programs and others.
Basics Linux commands
Directory commands
1. pwd Command
~pwd
The pwd command is used to display the location of the current working directory.
2. mkdir Command
~mkdir <Folder name>
The mkdir command is used to create a new directory under any directory.
3. rmdir Command
~rmdir <directory name>
The rmdir command is used to delete a directory.
4. cd command
~cd --> change directory to the home directory.
~cd <path to directory> --> change directory to the provided path.
~cd .. --> change directory to previous directory.
~cd ../.. --> Change directory to 2 levels back.
~cd - --> Go to the last working directory.
Listing Commands
1. ls command
~ls
The ls command is used to display a list of the content of a directory.
examples:-
~ls -l --> list the files and directories in long list format with extra information
~ls -a --> list all including hidden files and directory
~ls *.sh --> list all the files having .sh extension.
~ls -i --> list the files and directories with index numbers inodes
~ls -d */ --> list only directories.(we can also specify a pattern)
Thanks for reading! Hope you find this helpful.
Suggestions are always welcome! Happy Learning!!!
~Sumit
#linux #Devops