There are no terms used only by gay people and not straight people. But if you're talking about gay slang, Here is a list of Gay Slang Terms.
Gay IS a slang term! It means homosexual. Some other slang terms for homosexual men would include queer, fruit, drag queen, nancy, or pansy.
Lingo is slang for language. So it would mean various slang terms that gay people use among themselves.
If you're gay, you're gay. You don't "turn into a lesbian," you just come out of the closet.
A person who is not a gay and lesbian :) She is also awesomethe person who put her as a gay lesbian is a gay lesbian
There are many different gay and lesbian activist groups. The largest gay and lesbian group is currently GLAAD. There are many other different groups like GRIN as well.
The words "gay" and "lesbian" mean the same thing.
If they did then they wouldn't be gay or lesbian now would they?
Yes, both terms are considered proper and non-derogatory.
You don't have this choice. If you are a gay man, you are a gay man. If you are a gay woman, you are lesbian.
Gay is a slang word for homosexual
In some cases yes, especially if the "gay" bar refers to a lesbian bar. I think not because it is a gay bar. It would be a lesbian bar for girls.