Normally, HTML markup is used for displaying content in a web browser. “Rich snippets” are a format of HTML that allow you to carefully define pieces of information within a web page so that search engines and other programs know what the heck the data is good for.
Here’s an example of how you might normally introduce yourself:
<p>Hi there! My name is Shyam! Nice to meet you.</p>
Using Rich Snippets, we can tell search engines who I am using code like this:
<p>Hi there! My name is <span itemprop="name">Shyam</span>! Nice to meet you.</p>
You can define scores of items like logos, birthdays, product IDs, and much, much more. But, today I’m really only interested in me…or at least my standing as an author, so that my picture shows up prominently in Google search results.