Terminology and most used commands.

Formula
A formula is a package definition written in Ruby.
Keg
Installation prefix of a formula.
Cellar
Place where kegs are located.

brew list - See what's installed locally.
brew list --versions - See what's installed locally + version number.
brew info <formula>- Information on a formula.
brew install <formula> - Install a formula.
brew uninstall <formula> - Remove a formula.

brew outdated - See what's outdated.
brew update - Update Homebrew itself.
brew upgrade - Upgrade everything.
brew upgrade <formula> - Upgrade a specific formula.

brew cleanup -n - See what's going to be cleaned.
brew cleanup - Clean everything.
brew cleanup <formula> - Clean a specific formula.

Path of Homebrew binaries: /usr/local/Homebrew
Path of installed formulae: /usr/local/Cellar

• Homebrew homepage

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