MOUNTAIN VIEW, CA - SEPTEMBER 02: The new Google logo is displayed on a sign outside of the Google headquarters on September 2, 2015 in Mountain View, California. Google has made the most dramatic change to their logo since 1999 and have replaced their signature serif font with a new typeface called Product Sans. (Photo by Justin Sullivan/Getty Images)

Google is launching a new certification program for mobile site developers today. The exam covers everything from the basics of why mobile sites matter to how to improve mobile site speed, effective mobile UX design and more advanced topics like progressive web apps.

As Google notes, passing the exam is meant to show that you have “a demonstrated ability to build and optimize high-quality sites, and allows you to promote yourself as a Google accredited mobile site developer.”

A lot of the content in the study guide focuses on site speed. As Google notes, the majority of mobile site visitors will leave a site if it takes more than three seconds to load, yet the average load time for a mobile landing page is 22 seconds (and if those users leave without ever fully loading the site, they aren’t likely to click on any Google ads either, of course).

It’s worth noting that the exam doesn’t focus on Android, iOS or any other mobile operating system, though it does cover Google’s own Accelerated Mobile Pages project (and even though that’s a Google project, others are starting to support it).

The new certificate joins similar exams for AdWords and Analytics in Google’s Partner program (though the AdWords certificate is a bit more involved because you also need to pass more than one exam).