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This is a review of one part of the site only, so if anyone else wants to review the whole thing please go right ahead, it won't conflict with this.

Aside from its many other aspects, is the home of one of the most used HOSTS files around. And if you're troubled by ads that even your blocking software doesn't always get rid of, or there are certain kinds of sites that you don't want to see, ever, or you don't want your family seeing, then read on for an explanation of why this particular bit of geekiness is actually worth learning about. This takes a while, but it's worth the effort and believe me, you have no idea how much I left out because even I don't need to know.

IP Addressing:

Have you ever heard of IP addresses? You'll generally come across these in the context of web sites, as they are the numbers that hide behind the "" style of address. Every site has an IP address which is always in four groups of up to three numbers, and when you type "" into your browser and hit the GO button, another machine down the line has to go look up and get the numerical address for it, because computers don't think in English, only in numbers. Then the rest of the connection is made using numbers only, but all you see is in your browser address bar. OK so far? Just remember that machines need the numbers, they don't understand anything else, and the names we understand are "mapped" to those numbers.

So why don't we just use the numbers instead of messing about with all this "www" and "dot com" stuff? Simple. Nobody can remember even one string of numbers for long, let alone dozens or hundreds of them. But we can remember names. So we use names instead, but behind the names, there is always an IP address in the form 111.222.333.444.

The "Home" Address, or why there's no place like

Now then, every computer also has a number it uses to mean "me" and it's in the same format as an IP address, but if you enter it into a browser and hit GO, you won't go anywhere at all. Why not? Because this address is always your own address, so you end up back where you started and nothing happens. And this address is the same for every single computer out there including yours. It doesn't have to be different, because it just means "me" or "home" and isn't intended to take you anywhere or identify you to anyone.

This number is, and it's sometimes called a "loopback" or "looping" address because anything you send it's way simply loops back into your own lap again.

Using the Home address to redirect:

Now for the magic. Let's say, you want to stop your kid viewing a particularly nasty site on your computer. You simply tell the computer NOT to go to that site, but instead, go to Get it? It will just sit there and go nowhere. Now then, and you're probably ahead of me here, how about using the same technique to stop every single ad from a particular service? Easy - simply tell the computer what the addresses of the ad servers are, and tell it to go to if any of them are either typed in, or called from a web page. Once again, the computer will simply loop back to itself every time, and appear to be doing nothing. Unless you want to give the game away, nobody will know why they aren't going to their favorite porn site any more. And yes, if you're still ahead of me then you've figured that if that's possible, then you could also send them to some other site, wikipedia, say, or google, every time they tried to get to that porn site again.

The HOSTS file:

In Windows, all this is made possible by something called a HOSTS file, which is simply a list of all the sites you don't want to see and all the content you don't want served up to you, with instructions to either go to instead, or somewhere else of your choosing. Most commonly, the loopback address is used for simplicity. Your browser will serve up a "page unavailable" message for anything on the list, and you seldom have to worry about it again except to update the contents of that list every now and then.

Which all brings me back to, which saves you the trouble of building a list by having one already made up and kept bang up to date too. Which is just as well, because when you come to see how long it is, you'll be awfully glad you didn't have to type it up yourself! The site also provides instructions on how to find the file on your computer, depending on what operating system you have, and how to alter it. The hardest part of the whole business is just finding where MS have hidden the list, which is named HOSTS with no extension. In XP, it's buried at windows/system32/drivers/etc, which is about as far flung as you can fling a file in XP and hope to find it.

All you need to do is a copy-and-paste, opening your current file in Notepad and just pasting the new content in there. And you're good to go. If you want to take it further, of course, you can manually add sites that you personally don't want appearing on your computer; this is equally simple to do as each line in the file is a site you don't want, followed by the address you want to go to instead, which is generally But in any case, there are comprehensive instructions at which cover all flavors of Windows, and the page address is:

There's more information about the concept of the HOSTS file at, which also provides a very handy guide to finding this file on your computer regardless of the type of computer in use. And there's a warning there too which I'll repeat in case you don't get around to visiting the page: it is possible for malware to insert itself into a HOSTS file, redirecting you away from sites you choose to sites that IT chooses. It may for example send you to a malware site every time you try to go to Google. So it's important to make sure that your hosts file is read-only and nothing and nobody, including you, can write naughty things in there again until you give permission. In Windows, the way to do this is to go to the file icon and right click, select "Properties" from the mouse menu and then in the dialog box that appears, tick the "Read only" box and Apply. Don't forget to un-tick it again before trying to alter it next time.

You may be asking, isn't this the same as ad blocking applications and browser extensions? And yes, they share a great number of the addresses on each others' lists. But they aren't an exact match, and ad blocking is mainly just that, it doesn't protect you from whole genres, such as porn or those daft consumer review sites that are so popular these days. Plus, you can add and remove sites from your own HOSTS file, whenever you like, which I think makes it worth knowing how to do. I run ad blocking as well as a modified HOSTS file and get a better result from the combination, I think.

There are those who aren't too comfortable with modifying this file, I think the main reason being that it slows a machine down while ploughing through thousands of addresses every time you want to go to a website. Well, if you find that really is the case for you, go back to a blank file. But frankly I've yet to notice, on a modern machine with a fast connection, that my browsing speed has been noticeably reduced.

I hope this is useful to you and you'll give it a go, but if you do, don't forget to save a copy of your original HOSTS file somewhere, in case of an unexpected crash or error. Aside from that, and with apologies to anyone who knows how much of the technical cr*p I left out, you're done. Have fun :)

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