W3Schools doesn't really have a great reputation:
http://tinyurl.com/6pt83j
(http://zofbot.zoffix.com/cgi-bin/db.pl?search_term=w3schools&search_on=commands&db_section_css=on&db_section_html=on&db_section_js=on&db_section_dom1=on&db_section_dom2=on&db_section_perldoc=on&sort=1&number_of_matches=all&search=Search)
However, it should suffice as a (very) basic introduction.
-- F.
That's been discussed a number of times - take a look here:
http://www.tiddlywiki.org/wiki/Dev:Code_Editors
-- F.