Even older digital watches would outperform Stefan Priebsch's first computer. He holds an academic degree in computer science, is the author of several textbooks, and a university lecturer. Stefan has presented and keynoted at technology conferences around the world. As Co-Founder and Principal Consultant of The PHP Consulting Company (thePHP.cc), he helps his clients to develop software successfully. Stefan spends his free time abusing his electric guitar and researching agile home improvement.