I am currently writing an auto biography and was wondering about the legal use of first names. Do I need to change the names to use them or is it ok as long as I dont use last names? I am sorry if this is an over asked and/or stupid questions. I just have no idea. Thanks!
leaving off the last names won't do a thing to protect the privacy of those you're writing about, since it will be easily apparent to them and any who know them, who you mean... and that can leave you at risk of being sued if any of them don't like what you say about them or how you portray them... it's always best, imo, to consult a literary attorney before writing about real people who are not in the public eye... a consult fee is going to be far less than what it will cost to defend yourself against a libel or invasion of privacy suit...
You can, however, change their names altogether (first and last). The folks who know the specific details of your life and how their lives relate to it (that are in your story) will still be able to identify themselves, but the rest of the world will not. This is something often done by many creative nonfiction writers as a way to protect the identities of those they write about.
I actually finished reading George O'Dowd's second autobiography this afternoon and in it he mentioned that when he wrote his first book he had sent letters to everyone (still living) to say what he was writing about and to ask whether they would allow him to use their real names or if they would prefer him to change the names - he had mixed responses and (as far as I'm aware) respected each persons wishes. If you intend to publish then you might want to do the same but at the time of writing the first draft it's not entirely necessary.
which is exactly why it's wise to get permission, regardless of name changes... if their family and friends will know it's them, thanks to the time/location/events detailed and the author's name, then you can be sued for invasion of privacy, libel, et al. ... again, it's best to consult a literary attorney before going ahead with any autobiography/memoir, especially one that will show anyone in a bad light...