---
{
  "title": "Introduction to FHIR Terminology",
  "description": "The first post in a series on FHIR terminology, for readers new to coded values, code systems, and value sets.",
  "date": "2026-08-11",
  "author": "Orlando Osorio",
  "tags": ["Terminology", "FHIR", "Tutorial"],
  "extra-scripts": [
    "/assets/js/demo/termbox/base.js",
    "/assets/js/demo/termbox/intro01.js"
  ]
}
---

> For the complete documentation index, see [llms.txt](https://www.health-samurai.io/llms.txt).
> Use it to discover all available pages before guessing URLs.

---

This is the first post in a series about FHIR terminology. It's aimed at beginners. We'll start with the basics and then move into more advanced topics. We'll favor practical examples and real use-cases, and some posts will include interactive demos.

## Why

At Health Samurai, we've helped teams implement FHIR solutions for a long time. We've noticed that terminology understanding is often not as strong as it could be, and this causes implementers to go for complex approaches to solve problems that have simpler solutions within the FHIR terminology space. Although we've seen this across the board, it's most common on teams new to FHIR.

We think a possible explanation is that FHIR resources often map cleanly onto concepts a team already understands. Resources like `Patient`, `Condition`, and `Encounter` have intuitive counterparts in the healthcare domain. Once you get into `CodeSystem` and `ValueSet`, it becomes less obvious, especially since many systems treat coded values as database row ids or enums and have ad-hoc tables with admin CRUDs for maintaining lists of concepts.

The best way to learn FHIR is arguably to read [the spec](https://hl7.org/fhir). But the spec is formal and structured, organized as reference material, it gets dense fast, and sometimes it's hard to find a concrete example that makes it _click_.

With this series, we're hoping to provide a thread that beginners can follow into FHIR terminology, using concrete examples you can run, inspect, and adapt. 

## Contents

We'll start with an introduction to terminology in healthcare, then move on to the foundations of FHIR terminology. We'll go over specific concepts and resources, like coded values, code systems, value sets, and concept maps.

A few posts will focus on specific terminologies like SNOMED, LOINC, ICD; we'll also go over the HL7 terminology ecosystem: THO, UTG, and other acronyms.

Later on, we plan to dive deeper into more advanced topics like human language translation, supplements, syntactic code systems, and more.

### Interactive Examples

We'll use concrete examples and use cases throughout the series. Each one is live and runs against our Termbox sandbox instance. The demos will have a panel where you can explore the HTTP requests being run. Try the one below.

<div id="intro01-content">
  <label class="tx-label" for="intro01-input">SNOMED CT finding lookup</label>
  <div class="tx-context">Searching SNOMED CT for findings: descendants of <code>404684003</code> (Clinical finding)</div>

  <div class="tx-search-wrap">
    <input id="intro01-input" class="tx-search-input" type="text" autocomplete="off" placeholder="e.g. diabetes mellitus">
    <ul class="tx-suggestions" id="intro01-suggestions" hidden></ul>
  </div>

  <div class="tx-detail" id="intro01-detail" hidden></div>
</div>

## Next

This is the first post in the series. More are on the way:

1. [Introduction to FHIR Terminology](/articles/introduction-to-fhir-terminology) - _this post_
2. Terminology Basics - _coming soon_

We'll keep this list updated as posts publish. Questions or feedback? Please leave a comment.