Methamphetamine, is "crystal methamphetamine hydrochloride." It's pharmaceutical name is methylamphetamine or desoxyephedrine). From the media, you already know it as highly addictive synthetic drug.
Methamphetamine is cooked’ (technically "synthesised") in makeshift laboratories known as "clan labs" (technically clandestine laboratories), using precursor substances from other drugs (ephedrine or pseudoephedrine from instance) as ingredients.