Introduction about Servlet

Servlet is used to create web application, Servlet is robust and scalable because of java language, Servlet is a server-side programming language. it was many advantages of this technology compare to CGI (Common Gateway Interface)

Interfaces and classes in the servlet API

• Servlet 
• GenericServlet 
• HttpServlet 
• ServletRequest 
• ServletResponse

CGI(Commmon Gateway Interface) Vs Servlet

CGI

Disadvantage 

If number of clients increases, it takes more time for sending response.
For each request, it starts a process and Web server is limited to start processes.

Servlet

Advantage 

Servlet creates a thread for each request not process.
Servlets are managed by JVM so no need to worry about momory leak, garbage collection other services.