What is servlet

• Servlet is a web technology from Sun microsystems(On January 27, 2010, Sun was acquired by Oracle Corporation)
• Servlets is a Java based web technology to develop server side programs to make a website interactive.
• Servlet is an API.
• Servlet is aspecification.
• Any java based interactive website can be loaded into any brand web servlet without changing the single line of source code as web server is developed according to servlet specification.
• Servlet is a J2EE technology.

  Web container:

• Web container is a software that comprises of three modules 

1. web server
2. Servlet Engine/ servlet container
3. Jsp  Engine / Jsp container

Servlet engine:

• servlet  java engine is specialized software developed according to  specification
• A jsp engine is a  specialized software developed according to  specification
• jsp engine execute s jsps

General duties of servlet:

• To make website interactive a servlet performs the folowing duties in general

1. Capturing the user input
2. communicating with database
3. processing of data
4. producing a dynamic page
5. Handling over the dynamic page to the webserver