Top 10 APIs for Web Mashups

Mashups are web applications that combine data from two or more external sources into an integrated experience. Content used in mashups is sourced from a third party via a public interface or API. Many people are experimenting with mashups using Microsoft, Google, eBay, Amazon, Flickr, and Yahoo APIs, which has led to the creation of Mashup Editors.

ProgrammableWeb is a great resource on mashups. Based on their latest stats the top 10 APIs for web 2.0 mashups of all time are:

• Google Maps - to embed Google Maps in your own web pages
  
• Flickr - to present public Flickr data
  
• Amazon E-Commerce Service (ECS) - exposes product data and e-commerce functionality
  
• YouTube - access to key parts of the YouTube video respository and user community
  
• Virtual Earth - access to Microsoft's online mapping platform
  
• Yahoo Maps - developer APIs of Yahoo Maps
  
• Ebay - eBay Web Services and eCommerce platform
  
• 411Sync - SMS text messaging
  
• del.icio.us - social bookmarking
  
• Yahoo search - web, contextual and related search API
  

However recently popular mashups also use these APIs:

• Twitter - What are you doing?
  
• Skype - create applications that work together with Skype
  
• GeoNames - eight million geographical names available under free creative commons licence
  

Check out the full list with ~500 APIs on ProgrammableWeb and their tutorial on how to make your own web mashup!