Here’re some common environment variables:
|PATH||This variable contains a colon (:)-separated list of directories in which your system looks for executable files.
When you enter a command on terminal, the shell looks for the command in different directories mentioned in the $PATH variable.
If the command is found, it executes. Otherwise, it returns with an error ‘command not found’.
|LD_LIBRARY_PATH||LD_LIBRARY_PATH tells the dynamic link loader|
|HOME||Default path to the user’s home directory|
|EDITOR||Path to the program which edits the content of files|
|UID||User’s unique ID|
|TERM||Default terminal emulator|
|SHELL||Shell being used by the user|
You can find out more on Linux system ENVs at List of Environment Variables in Linux/Unix.