That's alright how else will you find out!...are you trained? Cos if you are im surprised your educator didn't tell you about these.
Basically an msds (Material Safety Data Sheet) is the health & safety sheets of your products you are using. Each product has its own sheet, it explains what chemicals are in the products, first aid measures, handling & storage procedures, how products should be disposed of, how product should be used (ie how to protect yourself against overexposure) and what to do incase of spills/fire etc.
If you are working in a salon your boss should have these, or if you are working for yourself you better get copys as you are required by law to have them. You should have a read through them and know about the products you are using. Have a look at the link above to get a better idea of what they are about.
hth
Michelle