A highly versatile word in the English Language.

Mistakenly thought to have come from an acronym "Fornication Under Consent of the King", the word most likely of native English origin, and is almost certainly of Germanic origin; Middle Dutch fokken (to thrust, copulate, or to breed), dialectical Norwegian fukka (to copulate), and dialectical Swedish focka (to strike, copulate) and fock (penis).

The word originally meant "to strike", "to thrust". Possibly becoming a euphemism for an older verb meaning "to copulate/breed" (likely from hyebh-; Sanskrit (yabhati) and the Slavic languages (Russian yebat`, Polish jebac)), the term took on the current meaning "to copulate".
The verb also means "to put into an impossible situation" in today's world ("You fucked us up!"), or as high praise ("fuckin' awesome!")

Even still, "fuck" is used as an expression of hate ("Fuck you!"), despite that copulation is really a pleasurable thing.
An expression of contempt:

......................... /´¯/)

......................,/¯ ..//

...................../... ./ /

............./´¯/'...'/´¯ ¯`•¸

........../'/.../..../... ..../¨¯..

........('(...´(..´...... ,~/'...')

.......................... ..../..../

..........''.............. . _.•´

.......................... ..(

.......................... .....

Translation of that pic: Fuck you!!


By the same token, this word has a great historical significance:
*Adam to Eve: Wanna fuck?
*General Custer: Have you ever seen so many fucking Indians?!?
*Captain of the Titanic: Where's all this fucking water coming from?
*Mayor of Hiroshima: What the FUCK was that?!?
*Todd Beamer: Fuck these assholes. Let's roll.
*Some American people: Obama just became president. Now that Obama is President we are all fucked.

I'm sure you can think of many more examples. With all these multipurpose applications, how can anyone be offended when you use the word. We say use this unique flexible word more often in your daily speech, It will identify the quality of your character immediately. Say it loudly and proudly! FUCK YOU!
Conclusion
The word of all words, the only word you can use in any situation.
Oh Fuck!!!!
( anger, excitement, sadness, confusion, stupidity, pleasure, disappointment, hysterical, boredom, exhaustion, happiness, fright, frustration, shock, being disgusted, depression, surprised, embarrassment, being ashamed, jealousy, loneliness, anxiousness, shyness, and anything fucking else you fucking people can feel!!!)

*Source: Urban English Class.
P.S. And in other languages, what is the "word"?