Expanding collapsing text

Some code I found to hide/display text. It'll come in handy in the future, I just don't know how. Source

Text for paragraph 1

Cool, it works with pictures!

Haha you can nest the tags!

I might use it to display post summaries, although Blogger already has a function for this. What I really want is to use text as the link instead of buttons and be able to nest text; I think that'd be great for keeping my notes, because that's how I think.

You can put the buttons anywhere: