Hi, TheMintyAltoids! I'd recommend Smeargle's Studio for more general art-related questions, but I'll chip in with my two cents here. :) Windows XP's MS Paint is a pretty fundamental program that I do 99% of my pixel art in (with the last 1% to use an external program to make the background transparent). More sophisticated options include Paint.NET, Aseprite, GraphicsGale.... There are many options out there!