Backlink

A backlink is an inbound hyperlink from another domain pointing to a page on yours. They are the original Google ranking signal — the entire PageRank algorithm was a model of which pages other pages chose to cite.

Not all backlinks are equal. Quality factors include the referring domain's authority, the linking page's relevance to yours, the anchor text used, whether the link is dofollow or nofollow, and where the link sits on the page (in the body is best).

Building backlinks ethically is slow but compounds. Tactics that work: original research with shareable data, link-worthy free tools, expert commentary that journalists cite, and broken-link replacement outreach. Tactics that don't: link farms, PBNs, paid links, comment spam.