You should read those if you are working on frontend

Frontend coding standard
http://na.isobar.com/standards/

Frontend development guidelines
http://taitems.github.com/Front-End-Development-Guidelines/

How javascript timers works
http://ejohn.org/blog/how-javascript-timers-work/

How prototype inheritance works
http://blog.vjeux.com/2011/javascript/how-prototypal-inheritance-really-works.html

Jquery Core Style Guideline
http://docs.jquery.com/JQuery_Core_Style_Guidelines

Jquery events misused
http://fuelyourcoding.com/jquery-events-stop-misusing-return-false/

10 things I learn in Jquery video