Reflection high-energy electron diffraction (RHEED) is the standard analytical tool of most molecular beam epitaxy (MBE) systems. A detailed analysis of RHEED patterns and oscillations can provide much more information about how growth proceeds than routinely exploited. Processes that take place during growth interruptions, the occurrence of a phenomenon denoted as 'material contrast', which has so far only been reported for II-VI materials, and a detailed analysis of the phase angle of RHEED oscillations are covered.