With the development of modern technologies, different kinds of application programming interface (API) are brought in Web 2.0 applications. API is an interface which aims to enable interaction with other software. A flexible website platform may facilitate data assembly and sharing. Consequently, API always fosters the innovation of developers themselves and third party developers.
Fotolia is the first worldwide social marketplace for royalty free stock images, allowing individuals and professionals to legally buy and share stock images and illustrations. 
As of October 2008, Fotolia had more than 800,000 members who had uploaded more than 4.2 million photographs and graphic illustrations. Fotolia has created an open Application Programming Interface (API). This API has made it possible for creative people to earn more money through affiliation (Partner API), to integrate Fotolia to your products or services (Business API) or to build applications (software, plugins, widgets) to simply improve the Fotolia experience (Developer API). There are so many possibilities. Fotolia provide the tools, now users can create the masterpiece.
Fotolia API services:
- Partner API
- Business API
- Developer API
- Reseller API
In order to use the API, you need an API key. The API key is required to do any query through the API. You can get an API key by going to the “Toolbox” section of your account and completing the API form. There are two examples of using Fotolia API services.
The Partner API allows people to create their own image bank and earn money through our affiliation program. With the API, users can search the Fotolia database, display results on their own websites, and generate revenue through our affiliation program.
The Developer API allows a creative person to design new applications such as modules, plugins, software, web services, or widgets. The API can also help to build a product or service to enhance or change the Fotolia user experience.
From the example of Fotolia, it is clear that Web 2.0 applications support web development by providing API services. It allows the combination of multiple services into new applications. As a consequence, API services could drive innovation from third party developers to contributing web applications.
References:
Kimi200100's Blog 
Great article you got there kimi!
I have never heard Fotolia before, now thanks to you. It seems that fololia is kinda similar to gettyimages.com, a more of a competition perhaps. It’s amazing these days for one can kick start working on things by simply using any of the given medias within your grasp. But it comes with a price i guess! Hopefully, we would see more freebies in the future! 🙂
Cheers,
Wan
Thanks Wan,
I just have a look at gettyimages.com. Yes, you are right. Both of these web image applications are similar to each other. However, I think the Fotolia is made for social marketplace share or buy of images. It has some impressive API services for providing much more innovation.
Thanks for commenting.
Great example Kimi and its a real move forward in the open data movement too. I am still curious as to who holds ownership over the images. Any ideas? If the site isn’t taking ownership I guess my next questions would be how does the site monetize.
Thanks Jack
Good question from your comment.
I think it is hard to define who actually holds ownership of images. However, the site provides a platform for users to share images which they would like to buy or sell. Site may make money from other business strategies, for example, advertisement.
Thanks for commenting