Who's Real?

Ever since I began writing short stories, people have been telling me they never know which of my characters are real and which are purely fictional.
The simple answer of course, is that they are all fictional, just some, more than others, are based more on either past experiences or are from tales I've heard other people tell.
At the end of the day, it doesn't matter and I'm pleased readers are gaining so much enjoyment from the results of my vivid imagination.
Some are real, some are not. I ...