Mashups are everywhere. Mashups are the next wave of web applications since not surprisingly, using the holy principles of web 2.0, mashups are not controlled by anyone and they are also free to use in a web development and in a production release.
Mashup can be seen in 2 views, user view, and developer view. In user view, mashup is a combination or mixed of contents from many sources. This can be live data displayed from many sources. Also in user perspective, the web experience is enhanced and often called as RIA (Rich Internet Application), bringing rich user experiences. From developer view, mashup is a combination of many web APIs into a single web application.
Sample scenarios:
- A web site of olympic games showing maps of Google Maps with the correct event and game schedules displayed for each city with the weather information. The event can be pulled from EVDB (Event Database), and can also be linked to Olympic news web services and Flickr APIs diplaying Olympic stadium for each city.
- A website of travel service showing Local Live map with the combined exotic places photos from Flickr. Also user can be given oprion to blog using Blogger API, directly on the same page.
An analogy of mashups can be seen on Windows APIs. Your desktop windows is a mashups of I/O API, User Interface API, and also other APIs such as Windows Service, Kernel, and GDI+. Only the mashup come from one source, Microsoft. Web mashup (often just mentioned as a single word of mashup)can come from different sources and mixed together. Most common web APIs heavily depends on REST, JSON, or simple SOAP. SOAP is slightly more complex to learn than REST and JSON, but it's available before them and more mature, since SOAP is a standard. Usually, mashup is also a working sample of AJAX application, since AJAX also uses REST, JSON, or SOAP.
Google developer, Aaron Boodman (the original creator of Greasemonkey script to alter web page) said, "The Web was originally designed to be mashed up, the technology is finally growing up and making it possible." More on this, read BusinessWeek article about mashup.
Today, mashup availabilites are growing at a very fast rate. Programmable Web has been recorded current rate (at the time of this writing), 2.84 mashups a day! Why? Because the ease of use and also the rise of REST and JSON uses in AJAX web applications, also the "unseen" agreement and collaboration among the provider of web APIs to be able to cooperate together. This mix can overlap one API and others, but that's the fun of creating mashup. You can create your own recipe for your own needs.
Additional resources: (most of them are taken from Wikipedia)
Sites about mashups
Software for building mashups
Again, comments are welcome! Illustrations about this are still designed to fit web size.