Difference between Web Server and Application Server:
1)Web server handles only Http requests where as Application server serves bussiness logic to application programs through any number of protocols.
2)Application server is more capable of dynamic behaviour than webserver.
3)web server serves web based applications.(i.e servlets and jsps) whereas application server serves web based applications and enterprise based applications(i.e sevlets, jsps and ejbs).
4)Web server is 3-tier architecture where as Application server is n-tier architecture.
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