The Economist September 17, 2005
Software: Programmers are combining data from different websites to create "mash-up" sites with entirely new capabilities
ARMED with a stack of house-listing printouts from Craigslist.com, a popular website, Paul Rademacher was driving around Silicon Valley late last year looking for a place to live. It was not until he was about to park that he looked up and realised he had already visited the same house earlier. Surely, he thought, there had to be a better way to evaluate and visualise a list of housing options.
And so there was. In February, Mr Rademacher-who by day was a software engineer at DreamWorks Animation-began building a website that combines the mapping capabilities of Google's search engine with housing listings from Craigslist. The result, HousingMaps.com, creates maps showing houses or apartments in a particular city within a designated price range. The site went live in April, and is a leading example of one of the latest internet trends: the web mash-up. HousingMaps instantly attracted a crowd and has since been visited by more than 850,000 people.
The term mash-up is borrowed from the world of music, where it refers to the unauthorised combination of the vocal from one song with the musical backing of another, usually from a completely different genre. Web mash-ups do the same sort of thing, combining websites to produce useful hybrid sites and illustrating the internet's underlying philosophy: that open standards allow and promote unexpected forms of innovation.
"Mash-ups are emblematic of the direction of the web," says Paul Levine, the general manager of Yahoo! Local, a subsidiary of one of the web's most popular sites. "This is about participants in the web community opening up their systems." It may also be about good business. By building their sites using open standards, and so making it easier for customers and developers to build other sites that plug into them, companies can both encourage innovation and boost their own popularity. "When you lower the barriers to entry, interesting things happen," says Tim O'Reilly, president of O'Reilly & Associates, a firm based in Sebastopol, California that publishes programming handbooks. "The players who figure this out will wield a great deal of economic power."
As often happens online, this trend is being driven from the bottom up, by users. Most mash-ups happen without the sites that supply the data even knowing about it. For example, Greg Sadesky, a programmer based in Quebec City, grabbed textual data from Yahoo! Traffic and map data from Google without consulting either firm, to create a mash-up (see traffic.poly9.com) that produces traffic maps. Similarly, Chris Smoak, who lives in Seattle, has mashed together several traffic, web-cam, transport-information and map sites to create Seattle Bus Monster, a public-transit site for the Seattle area (see www.busmonster.com). The rise of online journals, or blogs, has spurred the mash-up trend by bringing programmers together to discuss new ideas and tricks. Mr Sadesky credits the inspiration for his traffic-map mash-up to the blog run by John Resig (ejohn.org), which explains how to extract traffic data from Yahoo!'s website.
Mashing is getting easier for these after-hours programmers as big websites start to cater to their needs. ChicagoCrime.org, a mash-up that lets visitors view crime data by street, date, type and zip code on a map of Chicago, for example, said at the end of June that Google's decision to release an official method for linking to its maps had made the site far more reliable. Yahoo! opened up its map data in a similar way in June, and in July Microsoft unveiled a pre-release version of its mapping site, MSN Virtual Earth. It includes a "Community" button to help programmers create websites that incorporate data from Virtual Earth.
Such firms are happy to see their sites get mashed. At the Where 2.0 conference in San Francisco this summer, Brett Taylor, the product manager of Google Maps, noted that "everyone is doing it already"-so why fight it? "A mash-up lets a company like Google tap into the creativity of the world's programmers," says Nathan Torkington of O'Reilly Media, who was the conference chairman.
So will mash-ups march on? Only if they lead to revenue, some predict. "Something has to evolve," says Craig Donato, the founder of Oodle, a site with local buying, selling and donation listings. If the information being mashed is useful, he says, it is probably expensive for the originated sites to put on the web in the first place. At the Where 2.0 conference, Mr Taylor of Google said that programmers were free to use Google maps for mash-ups that were "free to consumers"-but added that his firm reserved the right to deliver maps with advertisements on them in future. Dave McClure of Simply Hired, a recruitment site based in Silicon Valley, says he expects the mash-up scene to change, just as the blogging scene did when Google's advertisement-placing service, AdSense, first appeared and "turned free content into a monetisable data source".
There are already signs that mash-ups have commercial potential. Simply Hired and the social-networking site LinkedIn, for example, have already mashed themselves together. If you are a member of LinkedIn and go searching for a job on Simply Hired, you can link from a job listing to a list of LinkedIn contacts who could get you an introduction at the company in question. As well as helping users to land a job, this mash-up should help the two websites to boost their traffic. And in August, Salesforce.com, a pioneering provider of business software that runs inside web browsers, announced Smashforce, an initiative to make it easier to incorporate its software into mash-ups. A firm could, for example, combine a list of sales prospects with a map, to help a salesman plan his route.
All told, the urge to mix things up should keep companies and programmers busy for the foreseeable future-too busy, sometimes, even to use their own mash-ups. Mr Smoak, who created his mash-up during evenings and weekends, says he never gets up early enough to take the bus to his day job, at Amazon. "I'm not an early riser," he says. "But if I stay up late I can do projects like this." And what of Mr Rademacher's housing search? The popularity of his website helped land him a job at Google, but has also kept him so busy that he has not had time for any more house-hunting.