Differences from HTML: XHTML Attributes

//XHTML attribute names must be in lower case
//this is wrong
<table WIDTH="100%">

//this is correct
<table width="100%">

//attribute values must be quoted
//this is wrong
<table width=100%>

//this is correct
<table width="100%">

//attribute minimization is forbidden
//wrong:
<input type="checkbox" name="vehicle" value="car" checked />

//correct:
<input type="checkbox" name="vehicle" value="car" checked="checked" />