A web server is the combination of computer and the program installed on
it. Web server interacts with the client through a web browser. It delivers
the web pages to the client and to an application by
using the web browser and he HTTP protocols respectively. We can also define the web server as
the package of large number of
programs installed on a computer connected to Internet or intranet for downloading
files using File Transfer Protocol, serving e-mail and building and publishing
web pages. A web server works on a client server model. A computer connected to
the Internet or intranet must have a server program. While talking
about Java language then a web server is a server that is used to support the
web component like the Servlet and JSP. Note that the web server does not
support to EJB (business logic component) component.
A computer connected to the Internet for providing the services to a small company or a departmental store may contain the HTTP server (to access and store the web pages and files), SMTP server (to support mail services), FTP server ( for files downloading) and NNTP server (for newsgroup). The computer containing all the above servers is called the web server. Internet service providers and large companies may have all the servers like HTTP server, SMTP server, FTP server and many more on separate machines. In case of Java, a web server can be defined as the server that only supports to the web component like servlet and jsp. Notice that it does not support to the business component like EJB.
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