There are two types of body waves: compressional (P) waves and shear (S) waves. Primary waves (P-waves) travel the fastest, so they arrive at the recording station (seismograph) first. Secondary or shear waves (S-waves) travel slower than P-waves so they arrive second.
Modified frequency modulation (MFM) is an encoding scheme used by PC floppy disk drives and older hard drives.
mobile device management (MDM) Mobile device management (MDM) is the administrative area dealing with deploying, securing, monitoring, integrating and managing mobile devices, such as smartphones, tablets and laptops, in the workplace.