Youtube video's in blogs

Ok, I did a search and couldn't find the answer, I am sure someone here will know.

How can I embed a Youtube video in my blog?  I use blogger, if it matters.
Also, this is perfectly legal right?  It is similiar to linking, I would assume.

As many YouTube videos as there are linked out there I can't imagine there's a problem with it.  Heck, we've got a few embedded in posts here.

One thing to watch out for though is that they may start embedding ads into the videos.  And occasionally videos get taken off of YouTube so it might be worth checking back over your YouTube posts every so often. 

Not trying to take away anything from your idea.  I embed YouTube and Google Video videos in blog posts all the time.