Rails and dates, are they stored in UTC by default?

What is the best way for me to handle dates and timezones in rails?

Scenerio: I have customers who purchase products on a website from all over the world, and when they log in they will be able to choose which timezone they are from.

So I believe I should be storing everything in the database at UTC, and then on the front-end I should be converting the dates to the users set timezone preference.

Are their any gotchas with Ruby and Rails and datetimes etc?

I'm new to rails, so I am looking for guidance on how to handle this properly.