Please print "User Guides" books again. You do not need to constantly update them:
Physical "User Guide" books were far more quicker and easier to use to get answers to questions on how to use Adobe Illustrator. The book form could come out ever two years at most, including new updates, when it reaches a certain amount of pages, start a new volume. If you already have this online, or in a PDF format, please let me know where I can find it on your website and if you do have it online, does it have an "index" to look items up? Or just a search window? Thank you.