Introduction To Unix

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Unix


 What is UNIX? 


UNIX (UNiplexed Information and Computing System) is a powerful computer command line Operating System based on “C “ language Originally developed in 1969 by Ken Thompson, Dennis Ritchie at AT&T Bell Labs. It is very popular among the scientific, engineering, and academic communities due to its multi-user and multi-tasking environment, flexibility and portability, electronic mail and networking capabilities, and the numerous programming, text processing, and scientific utilities available. 


Features of UNIX  


Multi-User Operating System 

 Multi-Tasking Operating System

 Portability 

 Job Control  

Hierarchical Structure ( Single Root )  

Case sensitive  

Device Independence  Security 


Unix Architecture


Hardware: This layer consists of all the hardware resources being used.

Kernal: The kernel is the heart of the UNIX system which manages the system resources and it communicates between hardware and software. It also handles the scheduling and execution of commands. 

Shell: It is a special program that provides you to interact with a UNIX system. It gathers input from the user, executes it, and then displays the output.It is the way for a human to interact with the operating system and tell it to start certain processes. An interpreter is used where we give the command for the operating from the set of all commands for which the definition has been defined and stored in the libraries.

Application Layer: It executes the given external applications. It is an outermost layer to execute the applications.


Directory Architecture

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