I\'ve been a professional software engineer for about a year now, having graduated with a CS degree. I\'ve known about assertions for a while in C++ and C, but had no idea t
Asserts are used to catch programmer (your) error, not user error. They should be used only when there is no chance a user could cause the assert to fire. If you're writing an API, for example, asserts should not be used to check that an argument is not null in any method an API user could call. But it could be used in a private method not exposed as part of your API to assert that YOUR code never passes a null argument when it isn't supposed to.
I usually favour exceptions over asserts when I'm not sure.