what is the difference between the functions of proxy server and firewall?

Question

Please explain me the similarites and differences between both of the them in very simple words. Thanx.

Answer 1

A proxy server acts as a gateway to the Internet for many computers, but hides their identity (IP address). It also enables network administrators to prohibit or allow certain activities like visiting particular websites or web applications.

A firewall has one primary purpose. It allows or disallows Internet traffic (transfer of IP packets) by opening particular doors called ports to a computer or computers located beyond the firewall. The Windows operating system has a firewall incorporated within it, but there are also many devices such as routers that direct Internet traffic to particular locations that also contain their own firewalls that perform the same or even stricter functions.

Both proxy servers (servers setup on physical computers) and firewalls (a feature of the operating system or networking device) sit between the Internet and the computers that they are designed to protect or administer network services to.

Answer 2

Firewalls stop things from entering (and exiting, if you have zone alarm and some other good firewalls) your computer. Proxy servers kinda act as a staging area before it enters your computer. While there, it may block some things (firewall-ish activity), so that is your confusions.

Answer 3

http://computer.howstuffworks.com/firewall.htm
and proxy
Server placed between a user's machine and the Internet. It can act as a firewall to provide protection and as a cache area to speed up Web page display