What

 "a collection of schemas that webmasters can use to markup HTML pages in ways recognized by major search providers"

Still What?

<div itemscope itemtype="http://schema.org/SportsTeam">
  <span itemprop="name">San Francisco 49ers</span>
  <div itemprop="member" itemscope
        itemtype="http://schema.org/OrganizationRole">
    <div itemprop="member" itemscope
            itemtype="http://schema.org/Person">
      <span itemprop="name">Joe Montana</span>
    </div>
    <span itemprop="startDate">1979</span>
    <span itemprop="endDate">1992</span>
    <span itemprop="roleName">Quarterback</span>
</div>

Why?

Semantics are important – They give content meaning

We want Google to know what our stuff means

We want other spiders to quickly find and index us

We want to get our most relevant content in front of people

Internally it helps explain content

How?

This is the best bit...

IT IS SO EASY!

Think about the data

Find the related schema

Make minor HTML adjustments

Test!

https://developers.google.com/structured-data/testing-tool/