What is the Mac app signature?

[Tiemo Hollmann TB]

Hello, beeing new to Mac development, I don't know what to put into the
signature in the standalone settings of OS X instead of the ????. Everything
I put into it, was again replaced by the four ????. I thought it would have
been something like my company name, but obviously it must be a special
syntax or content.

And could perhaps someone explain to me in short words, what the info.plist
and PkgInfo files are for on Mac? Are they necessary to start the
application or just for "info" purposes?

 

Thanks for sharing!

Tiemo