What does the "plus" sign in front of a phone number usually mean?

Question

ex: [phone]

Answer 1

It means somebody thinks they are being cool by imitating the Europeans, who do it for, well, no reason. It doesn't convey any information, and you certainly can't dial it.

Answer 2

Nothing, dial all the digits

where I live we have to dial 10 digits

so sometimes we use  [phone]

also see the + on international numbers