Unix/Linux Operating System Introduction

 

Unix is a computer Operating System which is capable of handling activities from multiple users at the same time. The development of Unix started around 1969 at AT&T Bell Labs by Ken Thompson and Dennis Ritchie. 

The main concept that unites all the versions of Unix is the following four basics −

·        Kernel − The kernel is the heart of the operating system. It interacts with the hardware and most of the tasks like memory management, task scheduling and file management.

·        Shell − The shell is the utility that processes your requests. When you type in a command at your terminal, the shell interprets the command and calls the program that you want. The shell uses standard syntax for all commands. C Shell, Bourne Shell and Korn Shell are the most famous shells which are available with most of the Unix variants.

·        Commands and Utilities − There are various commands and utilities which you can make use of in your day to day activities. cp, mv, cat and grep, etc. are few examples of commands and utilities. There are over 250 standard commands plus numerous others provided through 3rd party software. All the commands come along with various options.

·        Files and Directories − All the data of Unix is organized into files. All files are then organized into directories. These directories are further organized into a tree-like structure called the filesystem.

pwd Command

The pwd command is used to display the location of the current working directory.

mkdir Command

The mkdir command is used to create a new directory under any directory.

rmdir Command

The rmdir command is used to delete a directory.

ls Command

The ls command is used to display a list of content of a directory.

cd Command

The cd command is used to change the current directory.

cat Command

The cat command is a multi-purpose utility in the Linux system. It can be used to create a file, display content of the file, copy the content of one file to another file, and more.

rm Command

The rm command is used to remove a file.

 mv Command

The mv command is used to move a file or a directory form one location to another location.

rename Command

The rename command is used to rename files. It is useful for renaming a large group of files.

head Command

The head command is used to display the content of a file. It displays the first 10 lines of a file.

tail Command

The tail command is similar to the head command. The difference between both commands is that it displays the last ten lines of the file content. It is useful for reading the error message.

 

 

 

 

 

 

 

 

 


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