Microdata is used to help get your site indexed and ranked more correctly on search engines.
Based on Schema.org microdata adds greatly to the SEO value of a site because it provides search-engines with information about the website content.
Microdata also makes rich snippets possible - which again can help your site stand out from others on the results page of a search engine service (like Bing or Google) and thus drive more traffic to you.
Small local businesses, such as restaurants and stores, and online retailers stand to benefit most from the inclusion of microdata. But it can be useful to any business having trouble generating traffic through search results.
The following global data fields has been marked up with micro data:
phone fax email company_name