software written above the level of the single device will command high margins for a long time to come."
Of course, any web application can be seen as software above the level of a single device. After all, even the simplest web application involves at least two computers: the one hosting the web server and the one hosting the browser. And as we've discussed, the development of the web as platform extends this idea to synthetic applications composed of services provided by multiple computers.
But as with many areas of Web 2.0, where the "2.0-ness" is not something new, but rather a fuller realization of the true potential of the web platform, this phrase gives us a key insight into how to design applications and services for the new platform.
To date, iTunes is the best exemplar of this principle. This application seamlessly reaches from the handheld device to a massive web back-end, with the PC acting as a local cache and control station. There have been many previous attempts to bring web content to portable devices, but the iPod/iTunes combination is one of the first such applications designed from the ground up to span multiple devices. TiVo is another good example.
iTunes and TiVo also demonstrate many of the other core principles of Web 2.0. They are not web applications per se, but they leverage the power of the web platform, making it a seamless, almost invisible part of their infrastructure. Data management is most clearly the heart of their offering. They are services, not packaged applications (although in the case of iTunes, it can be used as a packaged application, managing only the user's local data.) What's more, both TiVo and iTunes show some budding use of collective intelligence, although in each case, their experiments are at war with the IP lobby's. There's only a limited architecture of participation in iTunes, though the recent addition of podcasting changes that equation substantially.
This is one of the areas of Web 2.0 where we expect to see some of the greatest change, as more and more devices are connected to the new platform. What applications become possible when our phones and our cars are not consuming data but reporting it? Real time traffic monitoring, flash mobs, and citizen journalism are only a few of the early warning signs of the capabilities of the new platform.
7. Rich User Experiences
As early as Pei Wei's Viola browser in 1992, the web was being used to deliver "applets" and other kinds of active content within the web browser. Java's introduction in 1995 was framed around the delivery of such applets. JavaScript and then DHTML were introduced as lightweight ways to provide client side programmability and richer user experiences. Several years ago, Macromedia coined the term "Rich Internet Applications" (which has also been picked up by open source Flash competitor Laszlo Systems) to highlight the capabilities of Flash to deliver not just multimedia content but also GUI-style application experiences.
However, the potential of the web to deliver full scale applications didn't hit the mainstream till Google introduced Gmail, quickly followed by Google Maps, web based applications with rich user interfaces and PC-equivalent interactivity. The collection of technologies used by Google was christened AJAX, in a seminal essay by Jesse James Garrett of web design firm Adaptive Path. He wrote:
"Ajax isn't a technology. It's really several technologies, each flourishing in its own right, coming together in powerful new ways. Ajax incorporates:
AJAX is also a key component of Web 2.0 applications such as Flickr, now part of Yahoo!, 37signals' applications basecamp and backpack, as well as other Google applications such as Gmail and Orkut. We're entering an unprecedented period of user interface innovation, as web developers are finally able to build web applications as rich as local PC-based applications.
