[ Return to main course web page ]
[ Return to lecture schedule ]
The following text was taken from http://www.mcpcentral.com/ViewArticle.asp?ArticleId=50&PageNo=1, a page which seems to be no longer available on the web.
Introduction
This article is intended to introduce you to the concept of web services and where they might be used. It aims to answer the most commonly asked questions for those who have not been exposed to the concept of web services in the past.
What is a Web Service?
A web service is one or more elements of functionality that are accessible through the use of Internet standards such as XML and HTTP.
In a typical program you might use a set of libraries or classes that provide a set of functionality such as graphics, application logic, or access to an external service. In the new Microsoft .NET framework, this functionality can be provided as a web service, allowing the functionality to be accessible from any machine that's connected to the Internet, rather than just the set of machines that are nearby on the network. An additional benefit is provided because web services use Internet standards such as XML and HTTP, and therefore are not operating system dependant. So you can develop a web service running on Windows 2000 and use it from Linux or MacOS.
What is a Web Service Good for?
There are literally thousands of uses for web services. In general, you can think of web services as libraries functions and/or databases that you can access through the Internet. Here are a few examples:
Web services can be used to synchronize multiple applications written for different platforms in an enterprise environment.
Perhaps the best uses of a web service are those that nobody has thought of yet, as this exciting new technology opens many new doors. When HTML was first developed, nobody knew it would lead to the world wide web and a graphical browser that would change the entire world. It is expected that web services will change the playing field in the software industry.
Where Can Web Services be Used?
Even though the name is "web" services, there are many uses for web services from within normal applications. The good thing about web services is that they can be called from anywhere. You might develop a command line utility that calls a Star Finder web service to get all the information about a star or you might develop a full blown Star Information windows application, but use a web service to always get up to date info on stars rather than storing a the information on a static, local database.
So in short, web services can be used on web sites (as the name implies), but also in any other Windows, Linux, Unix, Mac, PalmOS, WinCE application or even command line utilities. Because web services use Internet standards, they are not tied to any particular operating system or programming language.
Where Do I Go Next?
The best way to understand web services, is to develop your own web service. So go download Visual Studio.NET Beta 1 (if you don't have a Universal MSDN subscription, you can request a set of CDs sent to you by mail) and read the article "Developing Your First Web Service in ASP.NET" that's available on MCPCentral.com.
As always, if you have comments on this article, feel free to send them to me at hamids@mcpcentral.com.