Aleena Bagwan

Unix is an operating system. It was developed in the 1970s at the  Bell Labs  research center by  Ken Thompson ,  Dennis Ritchie , and others.    Today there are more than 400 standard operating systems based on unix operating system (They are called unix like operating system) such as Linux,  Redhat,  Ubuntu,  Fedora,  Kali,  Macintosh,  and more.  Its mean if you know any one unix kernel based operating system you can operate all 400 standard operating systems. Unix commands ls  : To list all folders and files of current directory ls -l  : To list all folders and files of current directory with more details (with permissions and stuff) mkdir  : To create an new directory in current path touch  : To create a new file rm <YourFileName>  : To delete your file rm -rf <YourDirectoryName>  : To delete your complete folder   cd  : To change directory (go to inside a ...

Programming Languages ---------------------------------- Programming langauges are used to develop software applications (e.g. facebook, whatsapp, banking application etc) There are many programming languages like C, C++, Java, Python and more. Those who work on programming languages are called Software programmer or Software developer C language ========== -mother of all langauges -Denies Ritche -1972 Example (hellowo rd.c) #include   <stdio.h> void   main () {      printf ( "hello aleena" ); } Example : what is variable ? Example variable and datatype #include <stdio.h>      void   main (){          int   age = 12 ;      float   percentage = 76.99 ;      char   name []  = { 'a' ,  'l' , 'e' , 'e' , 'n' , 'a' };           printf ( "Name = %s" ,...