Under what circumstances do British police carry guns?

Question

I know that they have a reputation for not carrying guns, but it's my understanding that they do under limited circumstances. By the way, this question is coming from a Yank.

Answer 1

I was watching tv last night and this guy was yelling to british officer and the officer just told him to get in his car and go away.

If that was the U.S they would've tasered him, i thought that was funny.

Answer 2

If I remember correctly...they have be a special officer (I think a "firearm officer").

You are right, a normal British police offices (or constable) doesn't carry a gun. Once they have this position they can carry a fire arm.