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Why Do some Website Addresses have “www” and some Don’t? And Why Do some Work with or without the “www”?

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Why do some website addresses have “www”, and some don’t? And why do some work with or without the “www”?

Most of the time, it’s an oversight. Occasionally, it’s on purpose, but to be honest, I haven’t run across an “on purpose” in years.

It’s common practice now that “www” is optional; mostly because it’s redundant and URLs are long enough without adding redundant information.

But once upon a time, there was a reason.

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The original intent was that the “www” specified what you were trying to do, so you could be sent to the right computer to do that. Servers that were available for “World Wide Web” access used a “www” prefix. Servers that were available for “File Transfer Protocol” access used a “ftp” prefix. Even on the same base domain, www.example.com and ftp.example.com might well be completely different machines. The prefix was both a mnemonic device to help us remember what we’re doing as well as a way to route us to the right server.

The question, of course, is what to do when no prefix is specified. The way internet names work, www.askleo.com and askleo.com are technically two different names and two different sites. As the owner of the base domain name askleo.com, I needed to take a couple of extra steps to make them both behave the same way when you visit either with your browser.

Under ConstructionOver time, the web and all those “www” servers became the predominant traffic on the internet, so more and more sites began to respond to references both with and without the “www.” As I said, it’s become common practice, almost a pseudo-standard.

But unfortunately, “common practice” doesn’t imply 100%.

11 comments on “Why Do some Website Addresses have “www” and some Don’t? And Why Do some Work with or without the “www”?”

  1. i ws recently sent a web address to go to that was just a list of numbers: eg: 123.45.33.01 – but the page didn’t open…what is this kind of address?

  2. That’s an IP address. All computers on the internet are REALLY identified by IP addresses. The text names you and I use, like “www.ask-leo.com” get converted to IP addresses in order to really locate the computer. Most of the time you don’t need to know or care about this.

    Try it: http://207.46.250.119 will take you to the same place http://www.microsoft.com does.

  3. man i am facing this same problem. i can’t visit my website without using wwww infront of the url. i asked for help from my hosting service, but the guy said it is working fine. so it looks like it is just my computer. hah

  4. You wrote:

    The original intent was that the “www” specified what you were trying to do, so you could be sent to the right computer to do that. Servers that were available for “World Wide Web” access used a “www” prefix. Servers that were available for “File Transfer Protocol” access used a “ftp” prefix. Even on the same base domain, http://www.example.com and http://ftp.example.com might well be completely different machines. The prefix was both a mnemonic device to help us remember what we’re doing as well as a way to route us to the right server.

    One thing you gloss over is the reason that the “www.” has become so redundant — namely, that its function has been almost entirely replaced by the protocol declarator. the “http://” at the start of the URL now does what the “www.” once used to do; and of course, when “ftp://” begins a URL, the URL itself surely doesn’t need to insist on the pattern of “ftp.whatever.com”!!! The “[protocol]://” prefix has pretty much obviated the need for that sort of idiocy. Yet it’s still rampant!

    Hooray for force of habit, huh? 🙁 🙁 🙁

    • Completely wrong. The URL “scheme” (http, https, ftp, mailto, …) and the www subdomain both appeared at the same time – at the birth of the World-Wide Web. HTTP quickly became far more common than FTP or any other protocol, so web browsers now assume that when you type example.com you mean http://example.com/ (and the same for http://www.example.com). The www subdomain never meant anything special to browsers, it was just a convention, probably dating from the days when web servers were an experimental side-line rather than a company’s main point of presence on the Internet. Unfortunately the www convention spread around the world before companies realised that their web server was the server most deserving of the short example.com name. It was then blindly propagated by a million marketing departments who knew no better or thought it was trendy.

  5. As far I know for free domain www is not required and
    and vise verse.Is it correct?

    The article answers this. “Free” has nothing to do with it.

    Leo
    17-May-2011

  6. Hi there, thanks for the article,
    Im still struggling to understand how the domains with and without www are different. I have some websites and some load as www and some load without it. My webmaster tools apparently understands the two sites seperately. If I change my domain from example.com to http://www.example.com in the domain manager will the original links be lost?
    Thanks alot for your help
    Will

  7. As Leo says, *sometimes* the www. is redundant, sometimes it isn’t. It is the responsibility of the webmaster to straighten that out as Leo has, others have not. Probably it doesn’t make a whole lot of difference – except in one very important case: *secure* sites. A secure certificate for, say http://www.example.com will not work for example.com; they are different sites and the certificate ‘knows’ for which one it’s been issued for. More reasons to keep the webmaster happy.
    As to IP addresses to Hostnames, I like to use http://whatismyipaddress.com for those things. (no www ) Yes, that site tells *your* IP, but you can use the IP-Tools tab to look up any IP address (to see if it’s a host) or any Host name to see what IP address has been assigned to that host. That, plus a pretty good email tracer, make whatismyipaddress a keeper.

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