Simplifying interaction with the DOM is obviously a huge feature of jQuery. But also the functions are just very nicely laid out with the assumption you are doi

Simplifying interaction with the DOM is obviously a huge feature of jQuery. But also the functions are just very nicely laid out with the assumption you are doing web stuff. $(thing).doThis() is just so perfectly terse and understandable for what it's doing. Not just writing, I find jQuery to be very, very easy to understand and read.