posted 16 years ago
Hi Ganesh,
the book doesn't go into debugging, but as B Webb says, there's the excellent Firebug extension and also several debuggers for IE by MS. They allow you to set breakpoints, step in, out, etc, everything you could expect from a debugger.
Is there a good IDE with debugging built-in? That I don't know, in the past I've tried some Eclipse plugins, there was a one pretty decent one, there's also Aptana IDE which should be pretty good. Not a big IDE fan myself, I cannot recommend you something specific.