What does schema markup actually do?
Schema markup is a structured, standardised way of describing your business, services or content directly in your website's code, so search engines and AI tools don't have to guess what a page is about.
Think of it as a label written in a format machines can parse reliably, sitting alongside the words a person actually reads on the page.
A real example
This is the actual LocalBusiness schema Thommo.ai runs, trimmed to the fields that matter. It's the same JSON-LD format used across almost every major schema type.
{
"@context": "https://schema.org",
"@type": "LocalBusiness",
"name": "Thommo.ai",
"url": "https://thommo.ai",
"description": "Plain-English Answer Engine Optimisation checks and fixes for Australian trade and service businesses.",
"areaServed": ["Gold Coast", "South East Queensland"],
"address": {
"@type": "PostalAddress",
"addressLocality": "Gold Coast",
"addressRegion": "QLD",
"addressCountry": "AU"
},
"telephone": "+61457772172"
}What schema does not do
It doesn't guarantee a better ranking, and it doesn't guarantee an AI tool will recommend you. It's not a ranking signal you can max out. What it does is remove ambiguity: instead of a search engine or AI tool inferring your business type, area and services from scattered text, schema states it directly.
That matters most when the inference would otherwise be shaky, a site with thin copy, an unusual layout, or a business type that isn't obvious from the words on the page.
The types that matter most for a small business
You don't need every schema type schema.org defines. For most trade and service businesses, four cover almost everything worth marking up:
LocalBusiness — the business itself: name, area served, contact details.
Service — a specific service you offer, described on its own page.
FAQPage — genuine question-and-answer content, matched exactly to what's visible on the page.
AggregateRating — real review data, never fabricated or estimated.
How to check if your own site has it
Most sites either have none of this or have it half-implemented from an old template. The schema-markup check in the Once-Over looks specifically for LocalBusiness, Service, FAQPage or AggregateRating schema on the pages it checks, and tells you straight if it found nothing.
See where your own site stands
The Once-Over checks the specific things this article talks about, on your actual website, and tells you straight what's worth sorting first.