Contents 1. Introduction . 2. High explosives as pulsed energy sources. . 2.1. Explosives . 2.2. Detonators . 2.3. Explosive devices . 2.4. Explosively driven metallic pistons , 2.5. Experiments and experimental facilities 3. Generation of the initial field . 3 .l. Energy sources . 3.2. Coils for the capacitor-bank discharge. 3.3. Field diffusion in seamless resistive liners 4. Flux-compression experiments , 4.1, Strongly converging geometry: ultra-high fields 4.2. Essentially plane geometry: current generators 5 -1. Dynamics of the cylindrically imploding liner 5.2. Field diffusion and Joule heating 5.3. Discussion of experimental data and the turnaround phenom-5.4. Properties of liner materials and the highest achievable fields 6.1. Fast discharges into single-turn coils . . 6.2. Liners imploded by magnetic forces 7. Applications of megagauss fields in experimental physics 7.1. Solid state physics . 7.2. Particle accelerators and plasma physics . .