You have likely, at some point during your time at school, attempted to access a website and been redirected to some sort of "access denied" screen.  You reached this screen because of the school's network security: its internet shield.  A lot of you probably find it annoying, especially when it blocks you from content that seems that it should not be blocked.  What is this annoying shield here for?  It seems like it doesn't do anything more than deter us from accessing content from the internet.

The thing is, that is exactly what it's doing, and it does that for more reasons than those that seem immediately evident.  These days it is common knowledge that malicious data plagues the internet: spyware, adware, trojans, worms, et cetera.  Any one of these things slipping into the school's network could be potentially disastrous; secure information could be slipped to unwanted viewers; important data could be lost.  In other words, catastrophe.  The school's network censors certain websites because it doesn't want any of these bugs slipping through.

You're pretty careful you say?  You don't visit websites that have bugs?  I highly doubt it.  It's a common misconception that most websites don't have bugs; that if your computer doesn't start freaking out, you haven't caught anything.  Just about every website tacks some data onto your computer that isn't really wanted.  Cookies, as they're called, are like little spies that keep track of what sites you've been on.  These don't necessarily exist for malicious reasons -- they are actually there to improve what advertisements you see based on what you search for -- but they can still be dangerous if someone wanted them to.

I don't want to ramble; I just want to get across to you that school web shields are what you might call a necessary evil.  We might think we don't need them and we certainly don't like them, but it is for certain that they do much more good than harm.  The internet is a place full of deception nowadays.  Without a form of protection, even the most wary of web-surfers could unwittingly fall into a virus's clutches.