I'd just like to say, I'm sorry for being a grammar nazi here but this is a simple thing that everyone seems to get wrong and it just bothers me, it's not hard to get it right.
1) There is used to indicate location or presence, for example; "There is an OMA/DC tuber camping above B."
2) Their is used to indicate possession, for example: "B is their point now."
3) They're is used to indicate the current state of a group, being an abbreviation of 'they are', for example: "They're spawn trapped on B."
...is it obvious I play a lot of domination?
4) Your is used to indicate possession, for example: "Your claymore just killed someone capping B."
5) You're is used to indicate the state of one person, being an abbreviation of 'you are', for example: "You're not supposed to cap C when we have A and B!"
And, by (un)popular request:
6) To is used for verbs or a destination, for example: "I'm going to capture B." or "Their spawn has shifted to B."
7) Too is used to indicate something excessive or in addition to something else, for example: "There are too many campers in this game." or "I may as well start noob-tubing too."
8) 2 (or two) is a number, for example: "The stinger comes with 2 missiles." or "Why can't they make do with two grenades?"
And, because I felt like it:
9) Lose is used to indicate defeat, for example: "We are going to lose this match because we are spawn trapped."
10) Loose is used to indicate something being slack (i.e. the opposite of tight), or (far less commonly) in archery as a verb, for example: ""After a particularly frantic game of Modern Warfare 2, I often find that my bowels are loose" or "If you tube me from across the map again, I am going to loose this arrow into your face."
And, hopefully finally:
11) Which, a word indicating an option, for example: "Which of these assault rifles is best at long range?"
12) Witch, a female practitioner of magic, for example: "With the amount of air support being called in, the enemy team must either have a hacker or a witch."
13) Whether, similar to which, indicating an option, for example: "I don't know whether I should use the TAR-21 or the SCAR-H."
14) Weather, the current state of the local climate and a preoccupation of the English; for example: "The weather today is just awful."
15) Ridiculous, (the only correct spelling), the quality of being worthy of ridicule, for example: "Commando is a ridiculous perk."
16) Apostrophes are used to indicate possession or contractions of words like "is" "are" and "not", for example: "That guy's classes are just awful." or "There's a whole lot of noobtubing going on in this game." or "They're all just killwhoring." or "I can't bring myself to use a perk as cheap as commando."