Twitter vs. Tumblr vs. Flickr. What's the difference in function?

[hi]

So twitter is for images and short txts. I use it as kind of a nerve centre to see what's happening with the people i follow (famous, funny and personal friends).

What I don't get is why tumblr and flickr are so popular. Tumblr seems to be twitter with GIFs and without the word limits. I don't get what flickr is for at all... If you can upload ur images on tumblr why bother with flickr?

Can someone explain to me what the difference in function between (What you can do on one that you can't do on the other):
Twitter vs. Tumblr
Tumblr vs. Flickr
Flickr vs. Tumblr.

Thx.

[Terrell White]

Twitter- Shortly worded text- You cant argue or be rude on here
Tumblr- Photography and Blogging- Cant engage in conversations like Twitter
I have never used Flickr but its a photo sharing like instagram but for the internet
personally i dont care for Tumblr its boring neither do i care for Flickr, Twitters ok though