Shell script
Basics
Environment variables
How to read a value from user
Special variables
IFS effects on special variables
How to use 'cat'
How to use 'awk'
How to use 'sed'
How to use 'cut'
How to use 'uniq'
How to use 'sort'
How to use 'grep'
How to use 'find'
How to use 'jq'
How to use 'trap'
How to use 'crontab'
How to use 'let'
How to use 'wait'
How to use 'sleep'
How to use 'tee'
How to use 'xargs'
References