Short answer
SEO, AEO, GEO, AIO and GEM target different surfaces. SEO aims to rank in classic search results, AEO to be the answer in featured snippets and voice assistants, GEO to be cited as a source in generative engines like ChatGPT and Gemini, and AIO to appear in Google's AI Overviews. The first four are organic; GEM is paid placement there.
3 min read
Over the last two years, four new acronyms have entered search marketing. Most content uses them interchangeably, yet each describes a different surface, a different way of measuring and a different budget line. Let's clear up the confusion.
SEO: Search Engine Optimisation
Surface: the classic list of blue links. Goal: to rank and be clicked. Measurement: position, clicks, organic conversions. The most mature discipline and the ground the other four are built on. If technical infrastructure and content quality are not sorted out here, the rest has nothing to stand on.
AEO: Answer Engine Optimisation
Surface: featured snippets, People Also Ask, knowledge panels, voice assistants. Goal: to be the answer to the question. Measurement: the number of questions for which you hold the answer box, and a high-impression / low-click pattern. This is where zero-click search is addressed.
GEO: Generative Engine Optimisation
Surface: answers from ChatGPT, Gemini, Perplexity and Copilot. Goal: to be cited as a source in the text the model generates. Measurement: brand mention rate across a defined set of questions. There is no concept of ranking.
AIO: AI Visibility
Surface: Google's own AI Overviews and AI Mode. The reason for keeping it separate from GEO is practical: this surface is still fed by Google's search index, so classic SEO signals have a direct effect. Measurement: the queries for which you appear within the overview.
GEM: Generative Engine Marketing
Surface: paid placement and advertising inventory within generative engines. The other four are organic; this one is paid. The inventory is only just opening up; today's job is to keep a measurement infrastructure ready to test the channel the moment it opens.
How much budget for each?
There is no single right split; it depends on the category. But there is an order: first the technical foundation of SEO, then AEO (it extracts extra visibility from the same content at low cost), then GEO and AIO in research-heavy categories. For now, GEM is an experimental budget line.
- B2B services, healthcare, finance, software: GEO and AIO have a high impact.
- FMCG and price-led e-commerce: SEO and paid search still dominate.
- Local services: AEO and local entity signals take priority.
Frequently asked
- Do you have to do all five at once?
- No. If your category is not research-heavy, allocating budget to GEO early is inefficient. Measure first, see which surfaces you are visible on, then allocate the budget.
- Are these acronyms here to stay?
- The names may change; the surfaces will stay. What matters is not memorising the acronyms but being able to measure how many different surfaces your brand appears on.
- Does my agency need to do all of them?
- Splitting them across separate teams creates data silos. If they draw on the same measurement infrastructure, managing them under one roof is more efficient.
