The Java Servlet API allows a software developer to add dynamic content to a Web server using the Java platform. The generated content is commonly HTML, but may be other data such as XML.
Servlets are the Java counterpart to non-Java dynamic Web content technologies such as PHP, CGI and ASP.NET.
Servlets can maintain state across many server transactions by using HTTP cookies, session variables or URL rewriting.

In this module you will review how HTTP works to get information from a Web server to a user.
One of the most important aspects of HTTP:
Every request to a Web server is completely independent of the previous ones.
We will discuss three other major server side technologies and what a servlet is and how it functions.
After completing this module, you will be able to:

1. Describe how a Web browser requests information from a Web server
2. Describe how a Web server provides information to a Web browser
3. List some features of CGI
4. List some features of SSI
5. List some features of ASP
6. Compare servlets to other server-side technology
7. Describe what a servlet is