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.
1 The GFM is also called Molar Mass, Molecular Weight, and Formula Mass. 2  Sometimes it's called Formula Weight. 3  They all mean the same thing. 4  The GAM is the mass of one mole of a single element.