An SEO glossary of terms every marketer should know in 2026
A practical, current glossary covering the essential SEO terminology every marketer should be comfortable with, from foundational concepts to 2026-specific terms.
6 min read
The August 2018 core update, nicknamed Medic by the SEO community because of how disproportionately it affected health-related websites, is one of the most consequential updates in Google's history — not because of what it changed technically, but because of the standard it introduced: E-A-T, for Expertise, Authoritativeness and Trustworthiness.
Why health and finance sites were hit hardest
Medic disproportionately affected what Google's Search Quality Rater Guidelines call 'Your Money or Your Life' (YMYL) content — pages whose accuracy could genuinely affect a reader's health, financial stability or safety. Sites offering medical advice, financial guidance or legal information without demonstrable expertise or authoritative sourcing lost significant visibility, even when their content was well-written and technically optimised.
- Health and wellness advice without credentialed authorship or medical review.
- Financial guidance from anonymous or unverifiable sources.
- Legal information presented without qualified expertise behind it.
- Content on any topic where being wrong could cause real harm.
What E-A-T actually means in practice
Expertise asks whether the content's creator has genuine, demonstrable knowledge of the subject. Authoritativeness asks whether the site or author is recognised as a go-to source on the topic, by other experts and by the wider web. Trustworthiness asks whether the site is safe, accurate and transparent — correct information, clear sourcing, secure browsing and honest disclosure of who is behind the content.
E-A-T was never a single ranking factor you could tick off — it is closer to a lens Google applies across dozens of existing signals, weighted more heavily for topics where being wrong actually hurts someone.
The evolution to E-E-A-T
In December 2022, Google added a second E for Experience, updating the framework to E-E-A-T. This recognised that first-hand experience with a topic — having actually used a product, visited a place or gone through a medical treatment — is itself a credibility signal distinct from formal expertise. Our full E-E-A-T explainer covers this addition in more detail.
What a YMYL site needs to do differently in 2026
Author bylines with real, verifiable credentials; medical or financial content reviewed by a qualified professional; clear sourcing and citations to primary research; and transparent information about who runs the site and why they should be trusted. These are not optional extras for YMYL content — they are close to a prerequisite for ranking at all.
- Named authors with real, checkable credentials relevant to the topic.
- A visible review or fact-check process for sensitive claims.
- Clear citations to primary sources, studies or regulatory guidance.
- An accurate, transparent about page and clear contact information.
Google's own documentation
Google publishes its full Search Quality Rater Guidelines publicly, and it is genuinely worth reading the sections on E-E-A-T and YMYL directly if your business touches health, finance, legal or safety topics.
Frequently asked questions
Is E-A-T a direct ranking factor?
Not in the sense of a single measurable score. It is better understood as a quality framework that informs how Google's raters and algorithms evaluate many existing signals together, weighted more heavily for sensitive topics.
Does every website need to worry about E-A-T?
The strictest scrutiny applies to YMYL topics — health, finance, legal, safety and civic information. A recipe blog or a hobby site faces a lower bar, though basic trust signals still help every site.
Can a small business site with genuine expertise compete with larger, more authoritative sites?
Yes, provided it demonstrates real expertise and experience clearly — a named practitioner with genuine credentials on a small site can outperform an anonymous, larger site on a specific, narrow topic.
If you operate in a YMYL category and want an honest assessment of where your E-E-A-T signals currently stand, contact our team for a review.
The takeaway
If you operate in a YMYL category — health, finance, legal, safety — audit your author credentials and sourcing this quarter, since Medic's E-A-T standard still applies most strictly there.
Written by Fibvo — Bengaluru and Erode, India — working with clients in other time zones. Questions, or think we have it wrong? Tell us.
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