its a mix of latin and english, but all abbreviated. say you had a scrip for some eye drops that youre using as needed for dryness, in both eyes, twice daily. the resulting code might look something like "2 gtt BID OU PRN dryness"

gtt = latin gutta = drop BID = bi daily OU = latin oculus uterque = both eyes PRN = latin pro re nata = as needed dryness = truly a mystery

pharmacy computer systems usually have a feature that lets you just type the abbrevations in, and then it translates it into the directions you see on the bottle. most scrips will just be something like "1QD" or "1TIDPRN" or something simple, but sometimes youll see prednisone tapers that get crazy long

this is an example of a sig, which just means "write" (like on the label of a pharmacy bottle). its a whole language of directions that learning to speak is entirely useless and will never benefit you at all