Difference between Angle.p/pitch, y/yaw, r/roll?

Angle object.
Properties/fields (1, 2):
• p/pitch
• y/yaw
• r/roll

What’s the difference between the two?

There are no differences.

You can use both, .pitch and .p, I see no reason why you would ever use .pitch over .p though.

[editline]25th April 2015[/editline]

By the way, both of those wikis are outdated and contain a lot of incorrect info, use this instead - http://wiki.garrysmod.com/page/Category:Angle

I know I can use both to access the properties/fields. And I have readed all three known wikis - none of them stated any difference.
So, both (p and pitch) have existed in previous versions of Garry’s Mod?

As I already said, there are no differences.