External Hard Drive in OSX

Just bought my first Mac (mini) but it has a small SSD installed as the only drive (128gb). This is not enough storage for all my needs. Obviously I plan on keeping applications and the OS on that drive for the performance improvements, but my question is how OSX looks at external hard drives. Can I keep a 500gb external just permanently hooked up via USB and keep my music/video files on that? Will it index properly with searches? Is it a seamless experience with an external drive? Obviously it's a desktop unit so I'm not mobile with it.