Why blog???

A very good friend of mine,who was so kind enough to write about me, on her first blog is pestering me currently to start a blog myself...this has been the motiving factor for my first post
Why do ppl blog???
I have been trying to find an answer to this question for quiet sometime
Find below few of my guesses...
a)Some people like writing,they express their thoughts better on a paper
b)Few of them use their blog as a medium to brag their achievements
c)People like Sidin the most acclaimed blogger,tries to hone his creativity and writing skills by blogging and sometime he even gets his MBA project done ;)
d)Many of them blog, to jus express their views on any topic under the sky...afterall there is no authority above you deciding, what you should and what you should not say...
e)Some blog to make friends,meet new acquaintances,meet like minded people and jus generally improve their social life...
That sets my head whirling,why did i start a blog??
Jus for the fun part of it,and most important rite now,im in a mood to blog