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Firewall may refer to:a technological barrier designed to prevent unauthorized or unwanted communications between sections of a computer network

regards,

ratan

Right raran, but the concept is improved a bit,  firwall help your pc to protect treat of hacking or unwanted programm get access to your pc, or if anyway it get accessed, or virus infection happens it prevents and outword communication with its parents untill you authorized. For this you have to install an two way firewall. Normally in india people are still in the concept of one way firewall or no firewall at all. The default firewall of windows os is very week.

thanks 2 all

Firewall is a program which monitors all inward and outward traffic and grants access/ deny access. It can be compared to the security guard who checks on every vehicle entering or leaving a compound. We can program the firewall to allow authorised communications or disallow specific contents - for eg, many companies will block uploading of DOC/ XLS files from the company network to internet. 

Firewall can be either software based or hardware based or a combination of these. 

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