All four Aviary tools can be accessed using the API. "This means that whether people are creating images, vectors, color palettes, or visual effects, all of the functionalities of the tool are possible to access with no log-in required," says Derdik. So when a person navigates to a website that has integrated the tools, she doesn't need to have an account with Aviary.

Thomas McKelvey, who runs an online store called Milksites, says that he plans to integrate Aviary tools with his site soon. "We host online stores built for nontechnical users," he says. "Our clients need to resize, crop, and otherwise do simple touch-ups to product photos all the time. No other Web-based or desktop-based photo editor can seamlessly integrate with our software while also being easy to use."

Creating an open API is a strategy pursued successfully by many Web companies, including Flickr, the photo-sharing site, and Twitter, the microblogging service. Both of these sites opened their APIs to outside developers, and there are now hundreds of third-party tools that plug into their platforms. "Aviary is doing a really smart thing in opening its API," says Shawn Rider, manager of technologysolutions at PBS and an Aviary user. "They're clearly in tune with the trends."

"I couldn't really see Photoshop showing up inside a small-time T-shirt design shop on the Web," says Rider. "But at the same time, that's the sort of thing Aviary's API is designed for." He suspects that Aviary will push Adobe, which already has a minimal editor on the Web, to expand its Web-based offerings. "All these companies that had previously made bulky applications that lived on the desktop will have to think of ways to take advantage of the network," he says.

Aviary's Derdik says that the company will release a more advanced API that includes a way to authenticate users and let them access files stored on a company's own servers. "This is useful if someone wants to build an application that can track sources used, color information in a creation, and derivatives made," he says.