When visitors browse our website, they instinctively understand the meaning behind certain elements on the page. They understand when they are viewing a product page, reading reviews of our product, and even understand the difference between our recommended retail price (RRP) and our special price simply due to the layout of the page and how we have styled those elements.
Although search engines are becoming smarter every year, we can't rely on them to instinctively pinpoint the exact locations of these elements on our page. Microdata introduced with HTML5 helps to specify these elements for major search engines, such as Google, Bing, and Yahoo!.
Note
There are a number of different canonical tag vocabularies on the Internet that are compatible with major search engines. For e-commerce, one of the better vocabularies is called Good Relations, and is well worth taking a look at goo.gl/4R96K9.
The main reason why we would want to implement the schema.org structured...