Chuck Easttom spent many years in the IT industry, followed by three years teaching computer science and security at a technical college. He has since returned to industry as an IT manager with system security responsibilities. Easttom has authored eleven other books on programming, Web development, and Linux. His 20+ industry certifications include CIW Security Analyst, MCSE, MCSA, MCDBA, MCAD, and Server+. He has also served as a subject matter expert for CompTIA in developing or revising four certification exams, including Security+. Easttom currently teaches computer/network security courses at two colleges, and does additional computer security consulting work.