Symbols representing class name in xcode

Question

I am using Xcode 4.2, in which I created various classes that show various characters, such as ?, A, M with the name of the classes. The project is working absolutely normal. Nevertheless, I am curious to know the meaning of these symbols. Are classes with a question mark in the future creating an error or warning?

Answer 1

After many searches, I received an answer to this link in the section "Monitor the SCM status of your file."

M = Locally modified U = Updated in repository A = Locally added D = Locally deleted I = Ignored R = Replaced in the repository – = The contents of the folder have mixed status; display the contents to see individual status ? = Not under source control