An amp amplifies the signal.
A pre-amp is connected to an amp as a controller.(Volume, etc..) It would also have the connections needed for other audio equipment.(CD, etc..)
An integrated amp is a pre-amp and an amp all-in-one.
Neither a pre-amp, nor an integrated amp, have a radio tuner. A tuner would have to be added separately to p/u radio broadcasts. This is why the above products are called separates.
A receiver is a pre-amp, amp, and tuner all-in-one.
A pre-pro(pre-amp processor) is a pre-amp with AV connections for HT.
An AV receiver is a receiver with AV connections for HT.