# Extended Reality (XR) Resources on ZEEF > Human-curated extended reality (xr) resources resources by named experts. Not algorithm-ranked results. ZEEF is a human-curated link directory. Every page is built by a named person, not ranked by algorithm. Multiple curators can build competing pages on the same subject, so readers see multiple expert perspectives. ## Curator pages on this subject - [Extended Reality (XR) Resources by Marco Romero](https://extended-reality.zeef.com/maromero): Rebuilt from the internet's first collaborative VR database (2016). I'm Marco Romero — 3D designer and XR specialist. This is an unbiased, expert-moderated shortlist: no ads, no marketing, just what professionals actually use. - [Unity XR](https://unity.com/solutions/xr) — Industry-standard engine for XR development — cross-platform, rich asset ecosystem, and the XR Interaction Toolkit for rapid AR/VR/MR prototyping. - [VR/AR Association (VRARA)](https://www.thevrara.com/) — The leading global industry association for XR — connects enterprise adopters, developers, and hardware makers and publishes authoritative market research. - [Godot Engine](https://godotengine.org) — Open-source engine with growing XR support via OpenXR. Lightweight, MIT-licensed, and a serious alternative to Unity for indie and enterprise XR projects. - [Immersive Web Community Group (W3C)](https://immersive-web.github.io/) — W3C working group developing the WebXR spec. Follow here for official proposals, explainers, and the roadmap for browser-based immersive experiences. - [A-Frame](https://aframe.io) — Mozilla's open-source web framework for building VR and AR experiences with HTML and an entity-component system — runs in any WebXR-capable browser. ## About ZEEF - [Homepage](https://zeef.com): Sifting knowledge from noise - [Browse subjects](https://zeef.com/_/subjects) - [Meet curators](https://zeef.com/_/curators) - [FAQ as Markdown](https://zeef.com/faq.md)