Astrid pretty much summed it up...

Interest can be paid monthly, half yearly, yearly or at term. You're more inclined to get a higher interest rate if it's paid at term and also if it's a longer term. Interest can be paid back into the term deposit (so you are then earning interest on your interest) or into another nominated account. There is usually a fee if you have to access the funds before term.

I think the minimum term is 1 month and longest is usually 5 years. They are great if you have a lump sum sitting around waiting to be used i.e., house hunting, as it is a fixed rate and secure investment.

Can you tell I work for a bank?