"Given the amount of industry noise about native video and
scripted animations, you'd be forgiven if you had never heard of
the new microdata specification included in HTML5.
"Similar to outside efforts like Microformats, HTML5's microdata
offers a way of extend HTML by adding custom vocabularies to your
"The easiest way to understand it is to consider a common use
case. Let's say you want list details about a business on your page
— the name, address, telephone number and so on. To do that
you'll need to use some vocabulary in addition to HTML, since there
is no tag."