What's a Pocket?

That's right folks, I just asked the most stupid question in the world.
I've seen this term being used so many times on TF2F forums, and I get really confused. I usually see something like this:
"My clan wants me to play pocket, but I'm not very good at soldier. What should I do?"
I can see that it has something to do with the soldier, but by the context clues, I can't tell exactly what it is.
Is it a style of play? A strategy of winning? Please answer, I still have no idea.

Yours Confused,

dracollama

It's the soldier that stays with the medic in 6v6.

Pockets prevent Scouts from killing me...in theory.

Quote:
This is usually why you need a good soldier to play pocket. It IS a slightly different style of play for the soldier so it takes a little getting used to. Just remember, YOU ARE THE MEDIC'S BITCH, not the other way around...

Yeah, like the other guys say, it's a bodyguard for the medic. Soldier is usually best at keeping scouts away from the med. Not necessarily best at killing them, but can keep them pushed away and out of killing range.

A pocket (short for pocket soldier) is a soldier who is dedicated to defending the team medic. They go everywhere together (usually) and the pocket will do anything to keep the medic alive.

if youre in the EU the pocket is the demo

These guys already explained it but I'll give a little more detail. The pocket soldier is (like said above) the soldier that protects the medic from enemies, mainly scouts. A regular 6 man team has two sollys, so the other soldier is called a roaming soldier. He normally goes off on his own and fights whoever, often the demo and other soldiers. If you're  playing pocket you do pretty much anything to keep your medic alive, that could mean jumping in front of a crit rocket. As a pocket solly you're normally the uber target too.

Are you guys serious?
That's Awesome!
That's pretty much the style of play I do.
And I have a lot of good medic buddies to go around with.
Thanks, all of you guys, this really helps.

NOTES:
-im2cool4u had the best interpretation.
-"YOU ARE THE MEDIC'S BITCH, not the other way around.." is the best quote ever.

-dracollama