Vortex electronics and SQUIDs Understanding the nature of vortices in high Tc superconductors is a crucial subject for research on superconductive electronics especially for superconducting interference devices (SQUIDs) it is also a fundamental problem in condensed matter physics. Recent technological progress in methods for both direct and indirect observation of vortices e.g. scanning SQUID terahertz imaging and microwave excitation has led to new insights into vortex physics the dynamic behavior of vortices in junctions and related questions of noise. This book presents the current status of researchactivity and provides new information on the applications of SQUIDs including magnetocardiography immunoassays and laser SQUID microscopes all of which are close to being commercially available. TOC:Introduction. Vortex in High Temperature Superconductors (HTSC). Observation of Vortices. New Aspects of Vortex in HTSC. HTSC SQUIDs. Applications of HTSC SQUIDs. Materials Technology for Vortex Electronics