Imagine you’re running a shop on a busy high street. One morning, Google, the landlord of the entire street, suddenly decides to change the rules about who gets the best spot, the shopfront. Unfortunately, you’re moved from a prime corner to a quiet side alley. Yesterday, thousands of customers walked by your store; today, you’re practically invisible. Today, you’re hidden in an alleyway, invisible to the crowd and the footfall tanks. That’s exactly how Google’s algorithm updates can feel like to website owners. One tweak in the system, and your site can either skyrocket to the top of the search results or tumble into obscurity.

But here’s the truth: Google’s updates aren’t designed to ruin your visibility or rankings. They’re meant to reward the websites that truly help users; those that deliver value, trustworthy information, useful content, and seamless user experiences. (Read more in SEO Series 13: White, Black or Grey Hat? Becoming a Holistic SEO.)

In this guide, we’ll break down the major algorithm updates that have shaped SEO, why they matter in 2025, and most importantly, how you can adapt your strategy to thrive no matter what Google throws next.

A quick story

Back in 2011, a content mill called eHow was dominating search results – they are everywhere. They published thousands of shallow “how-to” articles often written by non-experts, designed purely to rank for popular search queries and generate clicks, not to help people. If you Googled “how to tie your shoes” or “how to fix a leaky tap”, you’d likely land on an eHow post. and everything changed. Panda wiped out low-quality content farms almost overnight. Sites like eHow lost their visibility, traffic collapsed, and the entire “content mill” model had to reinvent itself.

This was the first of many reminders that SEO isn’t about gaming the system; it’s about aligning with Google’s mission: “To organise the world’s information and make it universally accessible and useful.” – Google

What Is a Google Algorithm Update?

Before diving into the timeline, let’s clarify what algorithm updates actually are:

• Google’s algorithm is a complex set of ranking systems and machine learning models that determine how websites appear in search results.
• Updates are changes to these systems either broad (core updates) or targeted (like Panda, Penguin, or Medic).
• Impact: They influence visibility, traffic, and revenue for businesses relying on organic search.

Google makes minor updates daily, fine-tuning results to improve accuracy. While most are barely noticeable, major core updates announced a few times a year, can shake up entire industries. And with ‘Organic search drives over 53% of all website traffic. So, if Google changes the rules, it can fundamentally affect the quantity and quality of online visits that any business receives’ (Badalyan, 2025).

Types of Algorithm Updates

• Core Updates: Broad changes affecting trust, relevance, and quality signals.
• Targeted Updates: Focus on specific issues like spam, mobile-friendliness, or site speed.
• AI-Driven Updates: Use systems such as RankBrain, BERT, MUM, and Gemini to better interpret intent and context.

In 2025, it’s less about chasing every tweak and more about building an SEO strategy resilient to long-term shifts.

Table 1: Google Algorithm Timeline (1998–2025)

Core Algorithm Updates (2018–2025 Highlights)

2018 Core (Medic): Reinforced E-E-A-T, especially for health and finance.
May 2020: Rewarded freshness and up-to-date pandemic-related content.
June–July 2021: Introduced Core Web Vitals — speed, interactivity, and stability.
March 2023: Prioritised firsthand experience and author credentials.
August 2024: Rewarded small publishers with authentic, user-first content.
Nov–Dec 2024: Penalised thin or mass-produced content; reinforced usefulness and originality.

Case Study: HubPages vs Healthline

• HubPages (2011): Lost over 50% of traffic after Panda due to low-quality, thin “how-to” content.
• Healthline (2018–Present): Benefited from Medic and Helpful Content updates thanks to expert medical authors, citations, and trust signals.

Lesson: Shortcuts might win briefly, but Google always rewards trust, depth, and expertise.

Google in 2025: The AI Transformation

The 2024 documentation leak revealed rare insights into Google’s internal ranking systems confirming what SEOs suspected: AI now plays a leading role. Today, Google doesn’t just index the web it synthesises it. AI-driven experiences such as AI Overviews and AI Mode (Gemini) are reshaping how users search:

• AI Overviews generate summarised answers for billions of queries.
• AI Mode allows conversational, ChatGPT-style interaction inside Search.

Zero-Click Searches

69% of news-related searches now end without a click (SimilarWeb, 2025). Google answers directly, meaning fewer visits for publishers.

Your new SEO goal: be the source that Google’s AI trusts and cites.

To achieve that:
✅ Write clear, definitive answers in your first 100 words.
✅ Use descriptive headings and schema markup.
✅ Include unique stats, quotes, and visuals that AI can reference.
✅ Build your author and brand entity authority.

Action Plan / Checklist

✅ Monitor updates regularly (Google Search Status Dashboard, MozCast, SEMrush Sensor).
✅ Audit your site quarterly for thin content, slow loading, or broken links.
✅ Strengthen E-E-A-T — add author bios, references, and proof of expertise.
✅ Diversify traffic sources — build email, YouTube, and social channels.
✅ Structure pages for AI readability (schema, headings, bullet lists).

Key Takeaways

• Google rewards people-first, expert, and trusted content.
• RankBrain, MUM, and Gemini shape how search understands meaning.
• Authority now depends on both brand and author credibility.
• Quality, clarity, and user trust are the only sustainable ranking strategies.
• 90% of clicks still go to Page 1 (Backlinko, 2024).
• Sites optimised for Core Web Vitals saw a 24% lower bounce rate (Google, 2023).
• E-E-A-T is mentioned in 72% of 2025 SEO ranking case studies (Bain, 2025).

Conclusion

Google’s algorithm is always evolving; powered by AI, voice search, and entity-based systems. But one principle never changes: if you focus on people, Google will reward you. Since 2018, Google has shifted towards continuous updates with smaller changes daily and broad core updates every few months. Prediction is impossible; adaptability is essential.

Focus on creating content that’s useful, original, and built for humans.

Download the free OTINGA Algo Tracker 2025 – a practical worksheet to monitor updates, audit your site, and stay visible even during turbulent changes.

References

• Bain, D. (2025) SEO in 2025: 106 of the World’s Leading SEOs Share Their No.1 Actionable Tip.
• Celis, V., Skylark, A., Bloomfield, B. & Ocean. (2025) SEO Tutorial for Beginners: Master the Essentials of Search.
• Melinn, C. (2025) ‘What is SEO?’ Digital Marketing Institute. Available at: https://digitalmarketinginstitute.com/blog/what-is-seo#heading_57597 (Accessed: 3 October 2025).
• Google (2023) Core Web Vitals & Page Experience Report.
• Google Search Central (2023) How Search Works.
• Kent, P. (2019) Search Engine Optimisation for Dummies.
• Moz (2023) ‘Google Algorithm Updates History.’ Moz Blog. Available at: https://moz.com/blog (Accessed: 3 October 2025).
• Williams, A. (2020) SEO 2020: Actionable, Hands-On SEO.
• HubSpot (2024) ‘What is Google Algorithm?’ HubSpot SEO Blog.
• Search Engine Journal (2024) Timeline of Google Algorithm Updates.
• Search Engine Land (2025) Google Core Update Analysis 2025.
• Backlinko (2024) Ranking Factors Study.
• Boyd, C. (2025) ‘Google Algorithm Updates: What Do They Mean for Brands and Marketers?’ Digital Marketing Institute. Available at: https://digitalmarketinginstitute.com/blog/2018-google-algorithm-updates-what-do-they-mean-for-brands-and-marketers (Accessed: 3 October 2025).