Alias is a command that lets you create command aliases, it is very useful when you usually use commands with options.
As an example in my case I use a lot these commands
In both cases the “-h” option makes the output be in Kbytes or Mbytes instead of bytes, so it is more human redeable.
To create aliases for this commands just need to enter.
alias du='du -h'
alias df='df -h'
df will be executed with its -h option.
If you need to de-alias the command just enter:
And the alias for du will be deleted.
To view a list of all aliases just type
alias with no arguments on the command line.