What is this usernoted process in my Macintosh? I've got a warning saying that I'm running out of my memory and had to "kill some process" today. I've been using this Mac for over 3 years and this is the first time I was warned this way.

I've noticed that there is a process named usernoted in my Activity Monitor. It seems it's eating a lot of my memory. What is this?

BTW, why is Finder and Dock eating so much memory?
That's actually not a lot of memory for usernoted, Finder, or Dock. "usernoted" is a known process and is installed with OS X. Do you mind telling how much memory you have, as well as what OS version? 
Also note that you clicked on the Compressed Memory column, rather than regular memory, which is a more accurate way of showing memory usage. Don't forget to show all processes (not just your processes).