[full version of article A Web Services Taxonomy
A Web Service, according to a standard definition, is "a software system designed to support interoperable machine-to-machine interaction over a network." 1
To put it another way, a Web Service is some useful service offered (usually) on the Internet, designed as a sort of building block
you can use any way you want.
So, for example, Google Maps
, a free service that dynamically draws maps of any location and locates addresses, has been used by thousands of people to build new services such as crime-report maps and real-estate listing tools,
Another way to wrap your mind around Web Services is to consider a range of well-known ones
and what they do. That's what the chart below does, with services such as Paypal, Google, Twitter, and Sabre, the airline-reservations system. (click on chart to see full-size):
This chart represents a taxonomy, or classification, of Web Services, constructed by characterizing all services according to two factors:
- Data quality: from simple/commodity to complex/unique
- Transaction level: from basic lookup to real-world transaction.
The full version of this article, A Web Services Taxonomy
(PDF 84k), defines what is meant by those terms, and discuss representative examples of Services that exhibit varying degrees of these characteristics.
Based on this, I suggest that the Services with the most usage, customer value, and/or revenues typically have more complex/unique data, and/or are more transactional.
See also the above chart in full size
, or the full article