Since the 1980s research on quantum computation has dramatically changed the theoretical perspectives of computer science. Quantum computers could enable unprecedented computational power and revolutionize our cryptographic systems, even our entire electronic communication. This textbook gives an introduction to the theory of quantum computation. The author has chosen an elementary and lean theoretical approach, presupposing mathematical and physical knowledge which is standard in undergraduate courses of scientific or engineering studies, in essence linear algebra and complex numbers. The necessary mathematical notions are given in the appendix. Contents - Strange quantum world, qubits und quantum gates - Quantum Fourier transformation and QFT algorithms - Quantum search, quantum communication, error correcting quantum codes - How to build and simulate a quantum computer - Density operators and measurements - Complexity theory and quantum logic Who should read this book? - Students of engineering, especially electronic engineering - Students of computer science, physics, or mathematics - Practitioners in business and economy who want to understand, apply, or evaluate this new technology