$ brew help
Example usage:
  brew search [TEXT|/REGEX/]
  brew (info|home|options) [FORMULA...]
  brew install FORMULA...
  brew update
  brew upgrade [FORMULA...]
  brew uninstall FORMULA...
  brew list [FORMULA...]

Troubleshooting:
  brew config
  brew doctor
  brew install -vd FORMULA

Developers:
  brew create [URL [--no-fetch]]
  brew edit [FORMULA...]
  https://github.com/Homebrew/brew/blob/master/docs/Formula-Cookbook.md

Further help:
  man brew
  brew help [COMMAND]
  brew home