What is the purpose of the trip code?
It is a verifiable method involving passwords and encryption to assure that Q, is really Q.
The trip code is the identifying “moniker” by which “Q” can uniquely and reliably + securely post and we can likely attribute + confirm such identity. 8ch allows posters to post totally anonymously or to associate a trip code with / from which they can then post. The anon community is very scrupulous about such and there was a controversy at one point which others (then seen to be detractors - cough, corsi, cough) then claimed was an opportunity for “fakes” to interject themselves (I’ve seen no evidence of such)