Some use cases: - simple sketch of a user interface - technical diagrams, like for showing how a data structure is implemented, or the (basic!) messages sent

Some use cases: - simple sketch of a user interface - technical diagrams, like for showing how a data structure is implemented, or the (basic!) messages sent between client and server, or the architecture of your network - working out examples, like drawing the chain of events that leads to something breaking due to a bug, or a simple example illustrating what you're saying - very short code (3 lines good, 10 lines bad) A whiteboard can be a tool to help you explain things. It should be used to augment what you're saying in words. It's very hard to put a diagram in someone's head using words, but much easier if you can draw on a whiteboard. You're right, though, that things on a whiteboard should be kept very simple. Lots of code, or very large diagrams, are liable to turn into a mess.