Off-Page & Links

A

• Anchor text

  Anchor text is the visible, clickable text of an HTML link (`<a href="...">anchor text</a>`). It is a primary relevance signal for the target URL. Types: exact match, partial match, branded, naked URL, generic ("click here"). Over-optimization on exact-match anchors triggers spam filters.

• Anchor text diversity

  Anchor text diversity is the ratio of anchor types — branded, naked URL, exact match, partial match, generic — across a domain's external backlinks. A healthy profile is heavily branded and naked, modestly partial, lightly exact. Excessive exact-match concentration is a Penguin-era spam signal.

B

• Backlink

  A backlink is an HTML link from one domain pointing to a page on another domain. It is the atomic unit of off-page SEO and one of Google's three named top ranking signals. The `rel` attribute (none, nofollow, sponsored, ugc) determines how Google treats the link's authority transfer.

• Black-hat SEO

  Black-hat SEO is search optimization that violates Google's Webmaster Guidelines. Tactics like cloaking, link buying, scraped content, doorway pages, and PBNs. High short-term leverage and high penalty risk. Reserved for high-burn-rate operations that can absorb domain loss.

• Broken link building

  Broken link building is a white-hat tactic: find a 404 link on a target page, contact the editor, and suggest your equivalent resource as the replacement. The pitch helps the editor (a real fix) and earns you a contextual backlink. Hit rates between 5% and 15% are typical.

C

• Co-citation

  Co-citation occurs when two URLs are cited (linked) together by a third source, even without a direct link between them. The shared source acts as an implicit relevance signal. A concept Google has explored since the early 2010s, drawn from academic citation analysis.

• Co-occurrence

  Co-occurrence is when a brand or term appears alongside specific topic keywords across the web, without requiring a hyperlink between the mention and the brand's site. An implicit relevance signal that helps search engines associate entities with topics and intent.

D

• Digital PR

  Digital PR is public-relations work aimed primarily at earning editorial backlinks and brand mentions in digital publications. It overlaps with traditional PR in tactics (pitches, data stories, expert sourcing) but measures success in linking root domains and share of voice, not column inches.

• Disavow file

  A disavow file is a plain-text list of referring URLs or domains submitted through Google Search Console's disavow tool, telling Google to ignore those backlinks when evaluating your site. After Penguin 4.0 (Sept 2016), most spam links are auto-neutralized, making disavow an edge-case tool.

• Dofollow link

  Dofollow is colloquial SEO shorthand for any HTML link that does not carry a `rel="nofollow"`, `rel="sponsored"`, or `rel="ugc"` attribute. It is the default link state — no markup is required. Such a link passes link equity and anchor-text relevance to the target URL.

• Domain Authority (DA)

  Domain Authority is a Moz proprietary score from 1 to 100 that predicts how well a domain may rank on Google. It is not a Google metric and Google does not use it. Treat it as a relative comparison tool between competitors, never as an absolute KPI to chase.

• Domain Rating (DR)

  Domain Rating is Ahrefs' proprietary 0-100 score reflecting the strength of a domain's backlink profile. It uses a logarithmic scale based on the quantity and quality of unique referring domains. Like Moz's DA, it is a vendor heuristic — Google does not use it.

G

• Guest posting

  Guest posting is publishing content on another site, usually with an author bio and a backlink to your own site. Legitimate when the post is topical, original, and editorially driven. Considered a link scheme by Google when industrialized — large-scale, keyword-anchored, paid-for placements.

H

• HARO (Help A Reporter Out) (HARO)

  HARO ("Help A Reporter Out") was a daily email service connecting journalists with expert sources for stories. Cision rebranded it as Connectively in 2024. SEO teams use it to earn high-authority citations and editorial backlinks by responding to source requests in their domain.

L

• Link equity

  Link equity is the ranking authority transmitted from one page to another through hyperlinks. It's the modern term for what was once called PageRank flow or link juice. Each outbound link on a page splits its available equity, so equity dilutes as the number of outbound links grows.

• Link rot

  Link rot is the gradual decay of links as pages move, sites go offline, or domains expire. It hits both your inbound link profile (links to you that stop working) and your outbound graph (links from your site that lead to 404s). A continuous loss SEO programs need to monitor and replace.

• Link velocity

  Link velocity is the rate at which a site acquires (or loses) backlinks over time. Sudden, unexplained spikes are flagged by spam filters as likely paid or programmatic patterns. Steady, varied growth signals natural editorial earning. The shape matters more than the absolute count.

• Linking root domain

  A linking root domain is a unique referring domain pointing at your site, regardless of how many individual pages on that domain link to you. Three different articles from the same publisher count as one linking root domain. The headline trust metric in most backlink tools.

N

• Nofollow

  Nofollow is a link-level attribute (`rel="nofollow"`) telling search engines this link should not pass ranking credit. Since 2019 Google treats it as a hint, not a directive — reserving the right to ignore it. Sibling attributes for more specific cases: `rel="ugc"` and `rel="sponsored"`.

P

• Page authority (PA)

  Page authority is a URL-level score estimating how likely a single URL is to rank in search results. Moz coined the metric as a 1-100 logarithmic scale. Google uses its own internal signals, not Moz's; PA is a correlated proxy, not ground truth. High PA does not guarantee ranking.

• Private blog network (PBN)

  A private blog network (PBN) is a network of seemingly independent sites built or acquired with the sole purpose of linking back to a target site the operator wants to rank. An explicit violation of Google's link-spam guidelines, hit by Penguin in 2012 and continuously since.

R

• Reciprocal linking

  Reciprocal linking is the arrangement where two sites link to each other, often by explicit agreement. A common tactic in the early 2000s, flagged as a link scheme since the 2012 Penguin update when used at scale or via link-exchange schemes. Natural reciprocation between genuine partners is fine.

S

• Sponsored link

  A sponsored link is any outbound link marked with `rel="sponsored"`. Google introduced the attribute in September 2019 as the required way to disclose paid, affiliate, or sponsorship-driven links. Non-compliance — using unmarked dofollow links for paid placements — risks link-spam filtering.

T

• Toxic link

  A toxic link is a vendor-defined label for an inbound link a tool considers potentially harmful — usually based on heuristics like spammy TLDs, no organic traffic, link-farm patterns. Google does not use the term and most toxic-flagged links don't actually require any action.

• TrustRank

  TrustRank is a 2004 Yahoo Research algorithm for separating reputable sites from spam, based on graph distance from a manually curated seed set of trusted sites. Never an official Google ranking factor, but its core idea — trust propagates through links — informs Google's trust signals.

U

• UGC link (UGC)

  A UGC link is any outbound link inside user-generated content marked with `rel="ugc"`. Google introduced the attribute in September 2019 to let publishers signal that a link came from a comment, forum post, review, or similar user-submitted area. Treated as a hint, similar to nofollow.

• URL Rating (UR)

  URL Rating (UR) is Ahrefs's per-page authority score, on a logarithmic 0-100 scale. It's the page-level analog to Domain Rating, computed from the quantity and quality of internal and external backlinks pointing at a specific URL. Useful for comparing individual pages, not whole sites.

W

• White-hat SEO

  White-hat SEO is search optimization aligned with Google's Webmaster Guidelines. Tactics that improve content quality, technical health, and earned authority. Lower individual leverage than black-hat shortcuts but compounding, low-risk, and the only sustainable approach for real businesses.