any good web sites to learn about motion???

Hello. I am new to motion and have plenty of questions. Can anyone recommend a website so I can read up and learn.
Things they talk about are Imaginary Axis, Virtual Axis and I have noe clue. Thank you.

My only experience has been with AB and I learned from manual 1756-RM007G-EN-P.

You can download it from www.ab.com

http://www.eod.gvsu.edu/~jackh/books/integrated/pdf/integratedbook.pdf

here is another excellent book

http://literature.rockwellautomation.com/idc/groups/literature/documents/at/drive-at001_-en-p.pdf

the second one is more specifically drives and calculations related to

Often times yuo could type in the terms used in Wikepedia and it'll provide some standard definitions