Jack Purdum teaches in the department of Computer Technology at Purdue University. He received his B.A. degree from Muskingum College and M.A. and Ph.D. degrees from Ohio State University (and Purdue still hired him). He has more than 25 years of teaching experience and has several awards for teaching excellence. He is a best-selling author of more than a dozen programming books and was president of a software firm that specialized in compilers and other programming tools. He also holds a U.S. patent for imaging software he developed and has served as an expert witness for the legal profession for more than 30 years .