What supplements/vitamins do you use?

[justnotsure]

Hi, I'm pretty new to the forum and I've seen alot of people say that they use certain supplements or vitamins for their hair growth. I would like to start doing the same, but I cannot figure out what the acronyms mean. If you know what these are, please inform me!! Also, if you use something not listed, please tell me what you use!! Also, could you tell me if it's a pill, or powder or lotion...and how you use it!!

I am currently at mid-neck length and my next goal is shoulder length...HELP!!

MN
MSM
MTG
Biotin