Glossary
The words behind a click
Defined by how the web actually behaves, including the parts that make the numbers less certain than they look.
3
- 301 vs 302
- Permanent and temporary redirects. The difference decides whether browsers cache the hop, which decides whether you can count it or change it later.
A
- Attribution
- Deciding which placement, campaign or channel deserves credit for an outcome.
B
- Back-half
- The part of a short link after the domain: the key the server looks up to find the destination.
- Bot traffic
- Automated requests to a link that no person made: previews, security scanners, crawlers and monitoring.
C
- CNAME record
- A DNS record that points one hostname at another, which is how a custom domain is attached to a shortener.
- Custom domain
- A domain you own, pointed at a link shortener, so your short links carry your name instead of the shortener's.
I
- IP geolocation
- Estimating where a visitor is by looking their IP address up in a database of allocated ranges.
L
- Link rot
- The steady failure of published links over time, as destinations move, sites close, or the service in the middle shuts down.
O
- Open redirect
- A URL on a trusted domain that will forward a visitor to any destination given to it, which attackers use to borrow that domain's reputation.
Q
- QR code
- A two-dimensional barcode that encodes text, usually a URL, so a camera can open it without anyone typing.
- Query string
- The part of a URL after the question mark, carrying key and value pairs that travel with the request.
R
- Redirect
- An HTTP response that tells the browser to go somewhere else, using a 3xx status and a Location header.
- Referrer
- The page a visitor came from, as reported by their browser in the Referer header, when it reports one at all.
- Referrer-Policy
- A header a site sends to control how much of its URL is passed on when someone follows a link away from it.
S
- Short link
- A brief URL that redirects to a longer one, used to make links shareable, printable, and countable.
U
- Unique clicks
- An estimate of how many separate people opened a link, as distinct from how many times it was opened.
- User agent
- A string a browser sends identifying itself, its version and the operating system, from which device and browser breakdowns are derived.
- UTM parameters
- Tags added to a URL's query string that name where a link was published, so analytics can tell one placement from another.