What are some examples of disjoint events?
Disjoint events (or "mutually exclusive" events, as my teacher calls them) are events which cannot occur at the same time.
For instance, suppose you pick one card from a standard deck of playing cards. The probability of getting a king AND queen is 0, because a normal playing card never has two faces on it.
Thus, "K" (king) and "Q" (queen) are disjoint events.
Hope this helps! :)