Linux

Linux is an operating system – similar to Windows or Mac. It is freely available and very popular amongst researchers and programmers. Since many of the scripts you write will be run from the terminal, a list of popular Linux commands can be quite handy:

• cd Used to change the directory (folder) which you have open. If I wanted to navigate to one of my directories I may write the command “cd /data/research/project”.
  
• ls List the contents of a directory.
• pwd Show the path to the current working directory.
• mkdir This command followed by a name creates a directory.
• rm Can be used to specify an empty directory or file you want to remove, for instance if you had a directory called ‘data’ you could delete it using “rm data”. If I wanted to delete all the files and directories in the directory “data”, I could use this command: “rm -rf data/*”.
• tar –zxvf file.tar.gz Used to unzip a file.
• chmod 777 filename.py Used to change the permissions on a file – this allows uses to read, write and execute this file.
• sudo su – Enable root user privileges. You’ll be asked to input the root password if you issue this command.
• cp firstname secondname Copy a file somewhere.
• mv firstname secondname  Move a file and rename it.
• ssh Log into another server using an SSH client through the terminal by inputting “ssh username@serveraddress”.