To tell to the operating system where to look for the files, you can use the variable
PATH. For example, to add a path you can write:
PATH=$PATH:/usr/games
export PATH
To synthesize a complex command in a simpler one, ypu can use
alias. For example, to resume the command
ls -aF --color
in a simpler
ls, you can write:
alias ls='ls -aF --color'
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