I have never understood why text books are 600 pages long. What is worse, after reading all 600 pages, the reader is typically more confused than when he started reading. Most topics are easily understood by anyone, as long as they are explained properly. This was my motivation for creating EngineeringNotes.net. It is a website that is working to provide “about 20 page” summaries of many college level courses. These can be used either as a “crash course” to a topic or as a review for someone who has seen the material before but would like a refresher.