Ever wonder what a command you are using is? Turns out linux has the answers for you!
Simply type whatis followed by the name of the command.
Examples:
$ whatis bc
bc(1) - An arbitrary precision calculator language
$ whatis brew
brew(1) - The missing package manager for macOS
brew-cask(1) - a friendly binary installer for macOSwhatis uses the man pages to search your entered query.
There is also a reverse search, which searches the descriptions of commands. For example say you are looking for a calculator:
$ apropos calculator
bc(1) - An arbitrary precision calculator language
dc(1) - an arbitrary precision calculator