**Where is the `make.defaults` file located?** The `make.defaults` file is located *in your profile.* > **Where is your profile stored?** > Your profile is stored *in the `/usr/portage/profiles` directory.* > > **What values do profiles set many USE flags to?** > The values that profiles set many USE flags to are *good, default values for a particular purpose.* **How do you override the defaults that are set by the profile?** To override the defaults that are set by the profile, *write the settings to `/etc/portage/make.conf` or `/etc/portage/package.use`.* **Is there a single `make.defaults` file that's used by Portage?** *No*, there isn't a single `make.defaults` file that's used by Portage. **What's the best place to go to learn more about Portage?** The best place to go to learn more about Portage is *the Gentoo Package Manager Specification (PMS).* > **What package contains the Gentoo Package Manager Specification (PMS)?** > The package that contains the Gentoo PMS is *`app-doc/pms`.* > > **What type of document is the Gentoo Package Manager Specification (PMS)?** > The Gentoo PMS is *a rigorous technical specification that package maintainers can rely on.* **What are two easy ways to see what a profile does?** Two easy ways to see what a profile does are by running: * `emerge --info`. * `emerge -epv world`.