What is this?
This is the deprecated legacy repository of Homebrew, the macOS package manager. It has been archived and split into two successor repositories.
Is this still the actual Homebrew project?
No, this is an archived shell left behind after a split. The package manager itself moved to Homebrew/brew and the formulae/packages moved to Homebrew/homebrew-core.
Where do I go to actually install Homebrew?
You should use the new repositories instead: Homebrew/brew for the package manager and Homebrew/homebrew-core for the formulae that used to live in Library/Formula.
What platform was Homebrew for?
Homebrew (and this legacy repo) targeted macOS.
Why does this repo still have 26k+ stars if it's dead?
It accumulated stars during the years it was the real Homebrew/homebrew repository before the 2013-2014 split into brew and homebrew-core; the star count is historical, not a sign of current activity.
What happened to Library/Formula?
Its contents were moved into the new Homebrew/homebrew-core repository, which now hosts the package formulae separately from the brew tool itself.
What are similar projects?
zerobrew, brew, homebrew-cask, npm, veet, ripgrep, pipx, alfred-workflows
Which topics is it in?
package-manager, homebrew, deprecated, command-line-tool, terminal, tool, cli, developer-tools, macos, open-source