Simple Text Effect Question

There’s a really neat text animation that I’ve been wondering about for awhile. I haven’t even tried to imitate it yet because I truely don’t know where to begin.

The effect I would like to know about is a sort of ‘type-in’ effect.

Here’s an example:

It’s the transition in animation of the menu on the left. It’s like the words are typed in but with a random changing letter at the end as they come in.

It’s a really neat effect and I’m wondering how it’s achieved.

Yes it’s my first post but I’ve been watchin the forums for awhile now.
I already searched and came up with nothing so don’t flame:angel::smiley: