1. The universally recognized "F word"
2. N. Implying complete and utter confusion
3. N. a really stupid person
4. V. To procreate
5. adj. Can be used to modify any word for more passion
6. Int. Expresses disgust
7. Int. Expresses complete suprise and joy
8. adv. Can be used to make a command more urgent

From "Monty Python"

Perhaps one of the most interesting words in the english language today, is the word fuck. Out of all the english words that begin with the letter 'f' ...fuck is the only word refered to as 'the f word... It's the one magical word. Just by its sound can describe pain, pleasure, hate and love. Fuck, as most words in the english language is derived from german ...the word fuieken, which means to strike.
In english, fuck falls into many grammatical categories:

As a transitive verb for intance ...John fucked Shirley.
As an intransitive verb...Shirley fucks.

Its meaning is not always sexual, it can be used as...

An adjective such as ...John's doing all the fucking work.
As part of an adverb ...Shirley talks too fucking much.
As an adverb enhancing an adjective ...Shirley is fucking beautiful.
As a noun ...I don't give a fuck.
As part of a word ...absofuckinglutely -or- infuckingcredible.
And as almost every word in a sentence ...Fuck the fucking fuckers.

As you must realize, there aren't too many words with the versatility of fuck...such as these examples describing situations such as:

Fraud ...I got fucked at the used car lot.
Dismay ...ahhh fuck it.
Trouble ...I guess I'm really fucked now.
Agression ...Don't fuck with me buddy.
Difficulty ...I don't understand this fucking question.
Inquiry ...Who the fuck was that?
Dissatisfaction ...I don't like what the fuck is going on here.
Incompetance ...He's a fuc...

An expression of contempt.

This is the infamous F-word. the first swear word anyone learns. it is the most versatile word in the english language, with most of its definitions not within the english language. it can be used any way you like, insert it in between any word, sentence, letter. it probably fits. the definitions below are some common usages and phrases.

1. v. to have sex
2. n. the act of having sex
3. adj. with suffix -ed. general derogatory meaning
4. a general insult
5. n. attention or care of (usually lack thereof)
6. v. to disregard, ignore (used with -it, -that)
7. v. to mess up, destroy, mangle, etc. (used with suffix -up)
8. exclaimation of emotion
9. derogatory dismissal
10. expression of confusion
11. very, extremely
12. n. a person you don't like
13. bother, agitate
14. v. to be in distress

The only word in the English language that can form a grammatically complete, stand alone sentence.

bush just became president.

the word of all words, the only word you can use in any situation.