What's the point of tumblr?

[eskimo]

So before I made a tumblr my friend told me it was a way to express myself freely and meet people in my interest groups. So after finally making one to see what all the fuss was about, I still don't get the point of tumblr, I'm just liking pictures(and re-blogging my favorites). Does this even matter? I mean I don't see a way to communicate with people in my interests group. Do I have to re-blog and add a message back? That's kind of dumb in my opinion. I also don't see a point in blogging my feelings or w/e when A.) no one is going to see it so why would you bother posting something no one is going to see(like writing a letter and never sending it - no point)? and B.) If I didn't keep my emotions bottled up almost all of the time, I'd sound like a whiny emo teenager(which I'm not).

So can someone tell me the point of tumblr or why people find it so entertaining or worth their time?