1. Servlets and JavaServer Pages

Java servlets were the first technology for producing dynamic Java web applications. Sun Microsystems released the first Java Servlet specification in 1997. Since then it has undergone tremendous change, making it more powerful and easing development more with each release. Servlets are at the base of web content for many Java EE applications. Servlets are Java classes that conform to the Java Servlet API, which allows a Java class to respond to requests. Although servlets can respond to any type of request, they are most commonly written to respond to web-based requests. A servlet must be deployed to a Java servlet container, be it a full stack application server or a micro container, in order to become usable. The Servlet API provides a number of objects that are used to enable the functionality of a servlet within a web container. Such objects include the request and response objects, pageContext, and a great deal of others, and when these objects are used properly, they enable a Java servlet to perform just about any task a web-based application needs to do.