jQuery Question

What is the syntax for boolean attributes, e.g. a checked checkbox, in HTML?

Sounds like a bit of a silly question, but I am wondering what is the best way of stating that a checkbox is checked/unchecked in HTML.

I have seen many different examples:

<input type="checkbox" checked="checked" />
<input type="checkbox" />

<input type="checkbox" checked="yes" />
<input type="checkbox" checked="no" />

<input type="checkbox" checked="true" />
<input type="checkbox" checked="false" />

Which browsers work with which ones of these, and most importantly, does jQuery figure out which box is checked in all 3?

The W3C spec seems to imply that just the checked attr being there is correct. Does that mean that checked="false" and checked="no" will still check the box though?



<input type="checkbox" checked>
<input type="checkbox" checked="checked">

For XHTML you have to use attribute/value matching pairs:

<input type="checkbox" checked="checked" />