What is abstract art?  There is no right or wrong answer to this question.  Abstract art is open to interpretation, and that is one of the beautiful things about it.

Understanding abstract art is easy: all it requires is an open mind and a big imagination.

Abstract art doesn’t jump out and yell, “Oh hi, THIS is what I’m all about.”  Instead, it requires you to have an open, inquiring mind; you must enter the painting and see where it takes you.

Abstract art gives you the freedom to explore the artwork and assign your own meaning to the piece. This intensely personal process enriches a viewer’s experience of an artwork.

“Everyone wants to understand art. Why not try to understand the song of a bird? …people who try to explain pictures are usually barking up the wrong tree.”
-Pablo Picasso

Here are some great references/sources on abstract art: Art Is Fun & Wikipedia