Emerge

Sync the Portage tree using the mirrors by fetching the latest differences

Sync the Portage tree using the mirrors by obtaining a Portage snapshot that is at most a day old

Sync the overlay and Portage tree using eix

Search for all packages who have "pdf" in their name

Search through the descriptions as well

List what packages would be installed without installing them

Install a specific version of a package

Upgrade the selected packages, dependencies and deep dependencies that are outdated or have USE flag changes

Update all packages explicitly installed, as well as their dependencies and their build dependencies, asking to proceed

Like above, except changes to USE flags will also be considered in determining what needs to be re-built

Remove a package and the dependencies that no other packages depend on

Remove a package but not its dependencies

Remove unneeded dependencies