Yeah, I'm a TEFL teacher. If I taught English to non-native English speakers say in Canada, then I would be a TEFL teacher. They are essentially the same.
The target audience of this site is primarily teachers who teach English to speakers of other languages. I chose ESL for the site name primarily because it's used a bit more and some of the larger sites similar to this one use ESL in their name. It's a bit more popular that EFL. Does that make sense?