The purpose of CS 42 is to provide an accelerated introduction for first-year students who are advanced and who possess more than average background in computer science. If you've completed this course, you will have learned the topics in both the general introductory course CS 5, as well as the second course CS 60, and possibly more. You are then eligible to take any course having CS 60 as the prerequisite.
You can find everything you need to know about the class by clicking on the links below.