Tim Berners-Lee, the founder of the web, wrote a classic article in 1998 that is still very relevant today. It is called “Cool URIs don’t change”. It is still important because it helps you plan your website development to protect your URIs even if you change the architecture of your website later.
What is a URI?
For the purposes of this discussion, we can say a URI is a URL or web address. URI is the correct term but URL is in common usage. The differences are technical and shades of grey in the real world.
Use a technology-agnostic URI
This means that you shouldn’t show any sign of the underlying technology you are using in the URL e.g. .php or .asp. This also means that you shouldn’t use .html or .htm. Yes, strange as it seems, avoiding this extension will allow you to present any file format in the future using the same URI if you remove the .html.
For example, if you have a page with the URL “http://example.com/citynames.html” and later you use php to dynamically assemble a list, you either have to redirect the old URL or let the old URL empty so it returns a 404 and gets dropped over time from the search engines.
A much better solution would be to have “http://example.com/citynames” and you can serve a html, php or even Excel file from the same URL.
Plan your hierarchy carefully
To quote from “Cool URIs don’t change”,
“Well, we found we had to move the files…
This is one of the lamest excuses. A lot of people don’t know that servers such as Apache give you a lot of control over a flexible relationship between the URI of an object and where a file which represents it actually is in a file system. Think of the URI space as an abstract space, perfectly organized. Then, make a mapping onto whatever reality you actually use to implement it. Then, tell your server. You can even write bits of your server to make it just right.”
In other words, if you move your files to another directory that is more logical and organized, that doesn’t mean you have to change the URI address. The files can be mapped back to the URIs.
Tim Berners-Lee’s article “Cool URIs don’t change” is an easy read and one that will help you if you are developing any domains.
