Display the type of a command (whether it is a built-in shell command or a separate executable program).
type command
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The type command tells you the type of a command-whether it is a built-in shell command, an alias, or an executable program. For example, I use alias ll='ls -l' to define the alias ll. Here is what I get when I check the type of the command ll:
type ll ll is aliased to `ls -l'