I want to know the answer to the following question:
There are two basic forms of data packet, what are they?
All the background I'm provided with is that "If a USB host does not receive a response (such as an ACK) for data it has transmitted, it does not know if the data was received or not; the data might have been lost in transit, or it might have been received but the handshake response was lost.". Is that enough to answer the question?