Backlink
A hyperlink from one website or page to a page on another website.
Links from relevant, trusted sites help search engines discover pages and judge their importance, and they send referral traffic, so earning them is a long-term driver of organic visibility.
A software vendor publishes an original benchmark of 2,000 support tickets, pitches it to five trade publications and earns 14 editorial links in two months, which it tracks in Search Console's Links report.
Link counts say little on their own; relevance and the linking site's quality matter more. Buying links or exchanging them to manipulate rankings violates Google's spam policies, and sponsored or user-generated links should be marked with rel attributes.
A backlink is an HTML anchor element with an href on another site pointing to your URL; its anchor text and surrounding content give context. Crawlers follow links to discover pages, and Google uses links as one of many ranking signals. Rel values such as sponsored, ugc and nofollow tell Google how the linking site relates to the target.
Systems Architecture
Google Search Central — Spam policies for Google web search — https://developers.google.com/search/docs/essentials/spam-policies; Google Search Central — Qualify your outbound links to Google — https://developers.google.com/search/docs/crawling-indexing/qualify-outbound-links