I've been a graphic designer for some time and I also do web design. I'm freelance mostly. I actually would like to start doing more development and was wondering about others experiences.

I know some people find it hard to go from creative to technical or vice versa and that is not really want I was inquiring about. What I wanted to know was what is the job of a freelance web developer like?

If you did not have formal schooling, did you teach yourself? Also from developers what is the best language to start learning after - HTML, CSS and Javascript? Would that be PHP?

What field of development is most lucrative?