Retailers can now show shoppers the items on their sites that have attracted the most Pinterest users’ “pins.” The image-focused social network is making this possible with a new API, or application programming interface, which is a set of software instructions for transferring data between technology systems.

The API also lets merchants show shoppers the most recent items on their sites that Pinterest users pinned, the most clicked-through pins on their sites and pins from specific search terms, such as “high heels.” The Pinterest content updates in real time. The social network says it will add more features over the next few weeks.

In addition to letting retailers feature Pinterest content on their sites, the API will also let Pinterest users repin images and post directly from merchants’ sites.

Wal-Mart Stores Inc., Target Corp. and ModCloth Inc. are among the first retailers to use the API.

Pinterest is the social network where consumers can pin images and pictures of products they like from around the web. They often accompany those pins with a brief description or caption that appears below the image. Consumers add their pins to boards, which are organizational tools used to group pins together around a particular theme—for example, “Thanksgiving ideas.”

“If someone’s looking for Thanksgiving recipes on AllRecipes.com, they’ll see the most pinned recipes from the site on the home page,” writes Jason Costa, developer relations manager at Pinterest, in a blog post. “Or, they could go to Zappos.com to see which shoes pinners covet most. You could use these APIs to show popular products on your home page or to curate your top articles and other content on Pinterest at any given time.”

Wal-Mart is No. 4 in the 2013 Top 500 Guide, Target is No. 18, ModCloth is No. 366.