The term "Firewall" originally came from the building trade and was typically a wall made of stones or bricks that was designed to confine a fire and protect the building by containing the fire in one place. It may not have always worked, but that was the general concept. In today's tech world, a firewall is something entirely different. Webster defines a firewall as "computer hardware or software that prevents unauthorized access to private data (as on a company's local area network or intranet) by outside computer users". In short, it stops the bad guys from getting in, while allowing you to get out. Almost like a security guard for your network or PC.

"But where does this security guard sit, and how does that affect my internet connection?" you might ask. The answer is quite simple.

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