Aaron Hillel Swartz

“ And when people who use such software find themselves having to write a URL on a t-shirt or link to something from an email, they create a redirect—a special URL who’s only purpose is to introduce people to the nightmarish randomnumber system used by their actual website. ”

“ Designing URLs is the most important part of building a web application and has to be done first. Encoded in their design are a whole series of implicit assumptions about what your site is about, how it is structured, and how it should be used ”

“ URLs are everywhere. Most obviously, they appear at the top of the browser window while people are using your website, but they also appear in a myriad of other contexts: in the status bar when someone has the mouse over a link, in search results, in emails, in blogs, read over the phone, written down on napkins, listed in bibliographies, printed on business cards and t-shirts and mousepads and bumper stickers. ”

“ But if your main nouns are subdirectories themselves, as with the user pages on Twitter and Delicious, it might make sense to break this rule. (More on this in a bit.) )
Numbers work well in cases where pages get created automatically (maybe you’re importing a lot of stuff, or you generate pages in response to emails or incidentally for other actions) or their titles tend to change, but in other cases you might prefer what’s called a slug. A slug is just a little bit of text that looks good in a URL, like “wrt/dfw” or “beyond-flash”. ”

“ You’ll note that all this discussion has basically been about nouns—the main things that make up your site, whatever those are (videos, blog posts, books) . There are typically three other types of pages: subpages (which drill down into some aspect of the nouns) , site pages (like about and help and so on) , and verbs (which let you do things with the nouns) .
Subpages are some of the easiest, and some of the most difficult. In the easy cases, you just indicate the subpage by adding a slash and a slug for the subpage. ”

“ URLs shouldn’t change (and if they do change, the old ones should redirect to the new ones) so they should only contain information about the page that never changes. This leads to some obvious requirements.
These were most famously pointed out by the Web’s inventor, Sir Timothy John Berners-Lee OM KBE FRS FREng FRSA (b. 8 June 1955, London, England) . During a miraculous Christmas break in 1990 that reminds one of Einstein’s annus mirabilis,Tim not only invented the URL, the HTML format, and the HTTP protocol, but also wrote the first web browser, WYSIWYG web editor, and web server. ”

“ So with Twitter, a user’s page is at:
http://twitter.com/aaronsw while their status messages get URLs like:
http://twitter.com/aaronsw/statuses/918239758 (Notes: The “statuses” bit is redundant and the number way too long.)
But things get more complicated when your nouns have more complex relationships. Take Delicious, where users post links under various tags. How should things be structured? ”

“ Whatever the reason, they end up rearranging their files and changing their directory structure, breaking all their URLs. Even if you’re just rearranging the site’s look, it takes a lot of discipline not to move the actual files around, probably more than you’re going to have. And setting up redirects for everything is so difficult that you’re just not going to bother. ”