What are key points to explain Unit Testing

Question

I want to introduce Unit Testing to some colleagues that have no or little experience with Unit Testing. I\'ll start with a presentation of about an hour to explain the concept

Answer 1

Remember to point out that Unit Testing is not a silver bullet and shouldn't replace other forms of traditional testing (Functional Tests etc) but should be used in conjunction.

Unit testing works better in some areas than others, so the only way to have truly comprehensive testing is to combine it with other forms.

This seems to be one of the biggest criticisms I see of Unit Testing as a lot of people don't seem to 'get' that it shouldn't be replacing other forms of testing in totality.