Web Services Overview

While HTML pages (or the HTML output generated by ASP.NET web forms) are meant to be read by the end user, web services are used by other applications. They are pieces of business logic that can be accessed over the Internet. For example, e-commerce sites can use the web service of a shipping and packaging company to calculate the cost of a shipment. A news site can retrieve the news headlines and articles produced by external news providers and expose them on its own pages in real time. A company can even provide the real-time value of their stock options, reading it from a specialized financial or investment site. All of these scenarios are already taking place on the Web, and major Internet companies such as Amazon, Google, and eBay are providing their own web service offerings to third-party developers. With web services, you can reuse someone else’s business logic instead of replicating it yourself, using just a few lines of code. This technique is similar to what programmers currently do with libraries of APIs, classes, and components. The main difference is that web services can be located remotely on another server and managed by another company.