Pug run?

Nay, I'm not a new player, but I'm not up to date with all the abbreviations.
Could someone just tell me what a pug run is?

PUG = Pick Up Group, a group of people who don't know each other and are randomly put together either by a group finder tool or by broadcasting messages requesting others to join them. This is to distinguish it from groups of players who play together on a regular basis.

So, a pug run is running a dungeon instance with a bunch of people you don't know. Sometimes (probably most times) that works great. It can be a lot of fun and it's certainly a good way to meet people. Other times the people you meet that way are ones whose gaming style is... well... not very compatible with your own, and it doesn't go so well.

Aaah, that explains it. Now all the pieces fell into place. Heh. ;) Thanks.