Categories Launch — Organising 40+ Simulations

What Changed

3D Simulations started as a flat list of experiments. After 40+ simulations those links became overwhelming — the homepage was a wall of tiles with no way to find what you actually wanted.

Today, every simulation belongs to a category. Each category has its own dedicated page with a live canvas hero animation, curated simulation cards, and links to relevant technical articles.

The Categories

There are 39 category pages in total. Each was designed with a distinct accent colour, a custom hero canvas animation, and curated content cards linking to related simulations and articles. The accent colours are not arbitrary — Physics leans indigo, Nature leans green, Quantum leans violet — so that after a few visits you can tell which section you are in just from the colour of the page before you have even read the heading.

Under the hood, category pages are generated from a single source of truth: a manifest that lists every simulation with its title, slug, difficulty and tags. That manifest now also drives the homepage grid, the search index, and the sitemap, which means a simulation only has to be added in one place to appear everywhere it belongs. Before this launch, adding a new simulation meant editing four or five separate files by hand, and it was easy for one of them to fall out of sync.

Why Categories, Not Just Search

We already had a search box, and it worked fine for people who knew exactly what they wanted. But most visitors do not arrive with a specific simulation in mind — they arrive curious about a topic, like "how does diffusion work" or "what does chaos actually look like." A flat search box is a poor fit for that kind of browsing. Categories let you start broad, see what exists in a field, and narrow down visually instead of guessing the right search term.

Each category page opens with a short plain-language explanation of the field, followed by a grid of simulation cards sorted roughly from foundational to advanced. So the Chaos & Fractals page starts with the logistic map — the simplest possible chaotic system — and works up to strange attractors and fractal dimension estimators. The idea is that you can read a category top to bottom and come away with a working mental model, not just a list of demos.

Kids Sections

A new Kids section groups simulations by age-appropriate content, with larger touch targets, simplified descriptions and no advanced math. Look for the 🟢 age badge on category pages. Rather than hiding the science, the Kids versions reframe it: instead of a differential equation for a pendulum, the copy talks about "push it and watch it swing back" — the underlying simulation is identical, only the framing and reading level change.

We picked the first dozen Kids topics based on what shows up in primary and early secondary school curricula: simple machines, basic circuits, the water cycle, and Conway's Game of Life as an introduction to patterns and rules. More Kids categories will follow as the main library grows, since every new simulation is now a candidate for a simplified companion version.