Especially in the days before audio recording and playback, music was often written out as a means of preserving and communicating it. To do this, a system of notation was developed that gives musicians the information they need to play music as the composer intended it.
(Hope it helps :) )
S.E.E stands for Signing Exact English.
It’s more visual sign but it is somewhat improvised. Certain signals will have different prefixes and the same root sign. Signers gain a bigger vocab this way but it takes longer
P.S.E is Pidgin signed English. This helps keep the pace when corresponding with speaking. So words that aren’t that meaningful to the sentence are removed.