URL structure

A URL is the address of a page and the least reversible decision in a website’s structure. Everything else — the design, the words, the menu label — can be changed without consequence beyond the change itself. Change a URL and every link, bookmark, search result and printed reference pointing at the old address stops working unless a redirect is put in its place.

That asymmetry is the reason URLs are worth ten minutes at the sitemap stage, and the reason they are almost never given it.

The anatomy of a URL: scheme, domain, path and fragment

URL stands for Uniform Resource Locator — the full address of a specific resource on the web — and it is built from a small number of parts most people never need to name individually but that a supplier conversation occasionally requires. The scheme (also called the protocol) comes first, almost always https today, followed by the domain — www.example.com, or example.com without the www — which identifies the server. After the domain comes the path, the part actually covered by the rest of this page, and occasionally a port number where a site runs on a non-standard one, which is rare for an ordinary business site. A URL can also end in a fragment — the part after a #, such as example.com/page#section — which points a browser at a specific spot on the page rather than a different page entirely, and is worth knowing about mainly so it is not mistaken for a separate address needing its own redirect.

What a good URL path looks like

Property	Why
Readable by a person	It is quoted on the phone, in emails and on printed material
Words, not numbers	An address made of identifiers tells nobody anything
Lower case	Some servers treat capitals as a different address, producing two URLs for one page
Hyphens between words	Hyphens separate words reliably; underscores and run-together words do not
Short	Long addresses get truncated in search results, messages and print
Describes the page	Not the platform, not the date, not the internal system
Stable	Contains nothing that will change while the page still exists

The last property does most of the work. An address containing a year, a campaign name, a product code or an organisational structure is an address with an expiry date built into it.

What goes wrong with a URL

Platform artefacts. An address containing the name of the system, a query string, an index file or a numeric identifier is describing the software rather than the business. It also makes migration visible to the customer: when the platform changes, every address changes.

Dates. A page whose address begins with a year looks stale from the second January after it was published, whether or not the content has aged. Removing the date later means changing the address.

Categories that are really departments. Organising URLs by the business’s internal divisions works until the divisions change, at which point every address either lies or has to move.

Duplicate addresses for one page. With and without a trailing slash, with and without capitals, with and without a query string on the end. Each variant is a separate address as far as a browser cache or a search engine is concerned, and the consequences are covered in the search readiness guides.

Encoded characters. Spaces, ampersands, apostrophes and accented characters all survive in an address as encoded sequences that are unreadable and easy to break when copied.

Depth in a URL

A URL can express the structure, and it does not have to. Both of these are defensible for the same page:

• A flat address, where the page sits directly beneath the domain.
• A nested address, where the parent section appears before the page name.

Nesting communicates the structure to a reader and creates an expectation: a visitor who deletes the last segment expects to land on the parent, so that parent should exist. Flat addresses are shorter and survive reorganisation better, because there is no parent segment to become wrong.

The practical rule is that commercially important pages benefit from short, flat addresses, and supporting material benefits from nesting that shows where it sits. That is the pattern this site uses, and it is a deliberate choice rather than a technical necessity.

The domain part of a URL

Everything above concerns the path. The domain itself carries a separate set of Australian constraints: who may hold a .au name, what relationship the name must have to the registrant, and the fact that it is licensed rather than owned. Those are on Australian domain eligibility, and they are worth reading before a name is chosen rather than after.

One structural point belongs here. Whether the site lives at the bare domain or at a subdomain is a URL decision with consequences: content on a subdomain is a separate address space, and moving it later is the same kind of migration as moving a whole site.

Changing a URL after launch

Sometimes it is unavoidable — a service is renamed, a structure is corrected, a business is rebranded. When it happens, three things have to be true.

1. A permanent redirect from the old address to the new one. Without it, every existing link becomes an error page.
2. Internal links updated to point at the new address directly. A redirect that is followed on every internal click is a repair the site keeps performing.
3. A record of what moved where. The redirect map is a document, and it is needed again at the next migration.

A redirect is a repair rather than a neutral operation. It preserves most of what the old address had accumulated; it does not preserve all of it, and it does not do anything about references the site does not control, such as a printed brochure or a directory listing.

What to ask a supplier about URLs

• What will the address of each page be? Ask for the list next to the sitemap.
• Does the platform allow addresses to be set by hand, or does it generate them?
• Will one page be reachable at more than one address, and what happens to the variants?
• If a page is renamed after launch, what is the process, and is it billable?

The last question is worth asking in the quote stage rather than discovering later. The wider set of questions to put to a supplier before signing is part of what write a brief any supplier can quote against assembles.

What to do next

Write the address next to each row of your sitemap before design starts. Read them aloud. Any address you would not be comfortable reading over the phone to a customer is an address to change now, while changing it costs a keystroke. The naming decision that feeds it is on what to call your pages.