Hi there. I was wondering if you could help me out here. I got a Groupon as a gift recently and I need to book an appointment soon but not sure of the terminology lol. Anyway, what is the difference between an all-over color and a single process color??? My Groupon says I have choice between the two.

I'm not an expert on this by any means, but I want to make sure I get exactly what my hair needs when I get there and not get disappointed. I do know for sure that I need my grays to go!! My hair is colored, needing my grays to match lol. So would those options help in my case?

Thanks to everyone for taking their time to help!