> For the complete documentation index, see [llms.txt](https://notes.mikaelsamvelian.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://notes.mikaelsamvelian.com/macos-setup/homebrew/usage.md). # Usage To install a package (or **Formula** in Homebrew vocabulary) simply type: ``` brew install ``` To update Homebrew's directory of formulae, run: ``` brew update ``` To see if any of your formulas need to be updated: ``` brew outdated ``` To update a formula: ``` brew upgrade ``` Homebrew keeps older versions of formulas installed on your system, in case you want to roll back to an older version. That is rarely necessary, so you can do some cleanup to get rid of those old versions: ``` brew cleanup ``` If you want to see what formulae Homebrew would delete *without actually deleting them*, you can run: ``` brew cleanup --dry-run ``` To see what you have installed (with their version numbers): ``` brew list --versions ``` To search for formulas you run: ``` brew search ``` To get more information about a formula you run: ``` brew info ``` To uninstall a formula you can run: ``` brew uninstall ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://notes.mikaelsamvelian.com/macos-setup/homebrew/usage.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.