During my undergrad years in the college town of Lawrence, Kansas, I once ate at a unique restaurant called Potato Mountain Café. Potato Mountain offered more than 100 varieties of mashed potatoes–including some only-in-a-college-town menu items such as “pepperoni pizza mashed potatoes.” In an unfortunate turn of events that left many couch potato co-eds with a severe loss, the restaurant closed shop in 1999.

So far, the Web’s version of Potato Mountain Café’s mashed-up specialties seems to be facing a more fortuitous fate. A “mashup,” according to Wikipedia, can be defined as “a Web site or Web application that seamlessly combines content from more than one source into an integrated experience.” And over the past year, thousands of sites and applications have appeared on the Web that fit the above definition.

These sites are the creative output of developers and programmers who take existing structured data sources from third-parties such as APIs and RSS feeds, then combine them and add a user interface to create easy ways to access, view and interact with previously unrelated data. 

The term “mashup” actually comes from the music biz, where it refers to DJs who mix together music from different sources to create a completely new song. But the easiest way to understand what we mean by Web mashups is probably just to play around with a few: 

• Rollyo uses the Yahoo! Search API and lets you create your own personal search engine restricted to specific URLs and tags.  You can also access and use personalized search engines created by celebrities and topical experts.
• BashR allows you to search for a term, then it provides results pages that mash together information from a combination of Wikipedia, flickr and del.icio.us–sources that all consist of user-generated material.
• Fifa World Cup 2006 Mashup takes the Yahoo! Maps API and combines it with 2006 World Cup soccer schedule data. And voila!, you can learn the where and when for catching your national team in action.

Mashups can take a variety of shapes and formats, but the common element among them is that they take existing data points and build new services out of them. For a list of more mashups to check out, go to the Yahoo! Gallery (beta) and also take a look at programmableweb. 

The Yahoo! Publisher Network openly supports developers and other Web entrepreneurs who are working to improve the quality of the Web. We love to see publishers like Ning as part of our network, as they are providing a free service to help people clone, customize and share mashup-style Web applications. We attended and hacked away at the first Mashup Camp, which took place February 20 and 21 in Mountain View, California (Click here for a robust set of discussion notes from the event).

We also fully promote the efforts of our sister group here at Yahoo!, the Yahoo! Developer Network which is working across Yahoo! to help Yahoo! teams expose APIs and data feeds for developers to access and mash together. And we’re thrilled to be part of an overall organization that supports not only the efforts of the Yahoo! Developer Network, but also structured internal company events such as Yahoo! Hack Day. This creative and fun day was focused around the idea of letting our own developers take a day every so often to flex their innovation muscles and build their own hacks and mashups. 

If you have a mashup that you want us to know about, please drop us a line. And if you don’t have a mashup yet, get the crazy “Web-DJ” developer side of your mind going and spin something off!

— Cody Simms, Product Manager