Is there a way to mark media used and unused in Final Cut Pro?

I know in iMovie, it's marked in orange but what about FCP?

Luis and BenB are right about the range of orange usage. There are other ways to determine if it is in use.

1. Switch the browser to list view with option+⌘2. The media in use will have a triangle mark on the left.

2. Click on the triangle mark and it will say “In use”. If it is not used, it will not be marked. Please try switching the browser display method depending on your usage.

You can see used ranges marked orange in FCP as well.

Yes, but you have to enable it. It is turned off by default.

Remember you can also do the opposite, only show unused media. I like this as I can start filling in b-roll and cutaways, and never use the same clip twice. This is a workflow that helps me speed up my workflow quite a bit.