Servlet	CGI
1) Request are handle using lightweight threads.	1)New process start for every new request which reduce the response time and compilation time
2) Servlet remain in memory even after they complete a response, so it is straightforward to store arbitrarily complex data between requests	2)When a CGI program finishes handling a request, the program terminates

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CGI (commen gateway interface)

Servlet:  They are programs that run on a Web server, acting as a middle layer between a request coming from a Web browser or other HTTP client and databases or applications on the HTTP server we can also called it as container of jsp to handle http request, handles response ,security for writing dynamic site.