What is a backlink?

A backlink is a link on one website that points to a page on a different website. If a local newspaper's article includes a clickable reference to a plumber's site, the plumber has one backlink from the newspaper. The same object has two names depending on where you stand: it is an outbound link for the newspaper and a backlink for the plumber. Nothing else distinguishes it. The words "inbound link" and "incoming link" mean the same thing.

Why search engines ever cared

Early search engines ranked pages mostly by the words on them, which was trivially easy to manipulate — you repeated the phrase you wanted to rank for. Links were harder to fake because they required somebody else to act. Google's original insight was to treat a link as a signal of endorsement, and to weight that endorsement by the standing of the page giving it. A link from a page that many other pages link to counted for more than a link from a page nobody references.

That model has been layered over heavily since, and links are one input among many rather than the deciding one. But the underlying logic survives: a link is a public, machine-readable statement that one site thought another was worth pointing at.

The distinctions that matter

Internal vs external. An internal link points to another page on the same site. It helps search engines find and understand your pages, and it helps readers move around, but it is not a backlink — no independent party vouched for anything. External links come from a domain you do not control. Only those count as backlinks.

Followed vs nofollowed. A link can carry an attribute telling search engines not to pass ranking credit: rel="nofollow", or the more specific rel="sponsored" and rel="ugc". Google treats these as hints. Comment sections, most social platforms, and paid placements are commonly marked this way. A nofollowed link can still send you real visitors — which is often the more useful thing anyway.

Editorial vs paid. An editorial link is one someone chose to give because your page was useful to their readers. A paid link is one you bought. Google's spam policies explicitly treat buying or selling links for ranking purposes as link spam, and expect paid links to be marked as such. This is the distinction most likely to cost you something if you get it wrong.

Anchor text. The visible, clickable words. They describe the destination to both readers and crawlers, which is why "boiler repair in Leeds" is a more informative anchor than "click here" — and also why identical, keyword-stuffed anchors across many sites read as manipulation.

Why quality varies so much

Two backlinks are almost never worth the same amount: a link's value depends on who gave it, whether the linking page is itself trusted, whether the topic is relevant to yours, whether it was freely given, and whether any real person will ever click it — which is why "number of backlinks" is close to a meaningless metric on its own.

For how that valuation works in practice, and what a link is actually worth, see how backlinks actually work. If you have no links yet and no audience, the practical starting moves are set out in how to get your first backlinks when nobody has heard of you.

Links are not the only route to being found. A public leaderboard where position is a function of verified spend is a different mechanism entirely — no endorsement is implied, and none is claimed. It is worth understanding which one you are actually buying.