I've never worked with .RAW images before. Help?

I shot a friend’s wedding in .RAW.
I’ve been wanting to learn and figured I’d give it a go.
Now I’m not entirely sure where to go from here.

Any free raw converter programs (PC) that you’d recommend?
What else do I need to know before I attempt to start editing?
Or should I just jump in?

Is it hard to get a handle on?
Or pretty much self-explanatory?