How can I make effects 'fade' in and out?

Okay, technically I’m not wanting fades, but unfortunately my brain today is, to put it bluntly, absolutely useless.

Anyhow, what I’m actually trying to find out is how I can set up my movie so that when I click on a button, the text fades in, then, when I click another button, the current item/text fades out and the new item fades in instead of just disappearing and the new transition starting.

E.G

I click the ‘info’ button and the Information blurb appears/fades in/whatever => click the… I dunno, ‘contact’ button => the Information blurb/whatever the item is on the page fades out => the Contact info/whatever fades/appears

Does this make any sense?