Immunocomputing as a new computing approach that replicates the principles of information processing by proteins and immune networks is introduced. In the first chapter of the book a sketch of key biomolecular mechanisms of information processing that remain out of the scope of computer science and artificial intelligence is presented. The second chapter develops a rigorous mathematical basis for immunocomputing. The main notion are formal protein and formal immune network. The mathematical notions for these concepts are quaternions and bilinear forms, The third chapter provides a theoretical framework for pattern recognition in immunocomputing. The main notion is binding energy between formal proteins. The extreme values of the binding energy present a solution to the pattern recognition task. The fourth chapter presents a theoretical framework for language presentation and knowledge-based reasoning by immunocomputing. The fifth chapter develops an immunocomputing approach to the modeling of natural and technical systems (natural proteins, computer networks etc.). The sixth chapter presents a number of immunocomputing applications (space navigation, ecology, infection control, security etc.). The seventh chapter suggest a hardware implementation of the immunocomputing approach in an immunochip as the core of a future immunocomputing.