I've been playing a character for quite a while and am at level 18. I'd like to start another character but don't want to lose the one I have. Can you have two characters at the same time and save games for both characters without overwriting or losing any games? If this is already covered in a post somewhere, please show me a link, I can't seem to find it. Thanks for any help.

Yes. You can have as many as you want, just be sure to save them in a different slot when you go to the menu and click "save."

The only file automatically overwritten is the auto save file.

I actually lost a character once by relying on the Autosave... he wound up in a subway with enemies on both sides of him, with low health and no stimpacks. No matter how many times I tried, I couldn't get him out.

But yeah, you can have as many characters as your system's memory permits. Dozens, if you like.

Thanks! Just what I wanted to know!