A .WRZ file is typically viewed as a VRML world (.WRL) that has been compressed with gzip, since VRML is a text-based 3D scene format capable of describing full worlds—shapes, textures, lighting, camera positions, and simple behaviors—and compresses extremely well, which led to distributions labeled .WRZ or `.wrl.gz`, and opening one generally involves using a gzip tool to unpack it into a .WRL file for VRML-capable viewers, ensuring referenced texture files remain in the correct relative locations for proper display.
A quick way to verify a real gzip file is to check whether it starts with the signature bytes 1F 8B, which strongly indicates a compressed stream consistent with WRZ being a gzipped WRL, and a frequent confusion comes from mixing WRZ with RWZ, since .RWZ is tied to Microsoft Outlook rule exports rather than 3D content, meaning a file from email migration may be RWZ, while something from a 3D or CAD workflow is more likely a true WRZ.
When people say a .WRZ is a “Compressed VRML World,” they mean it’s a VRML scene file—normally a .WRL, where “WRL” literally means *world*—that’s been gzip-compressed to shrink its size for storage or older web delivery, since VRML is a text-based 3D scene format capable of describing full environments with geometry, materials, textures, lights, viewpoints, and sometimes behaviors, and because plain text compresses extremely well, the ecosystem adopted .wrl.gz or .wrz to indicate a gzipped VRML world.
In everyday use, “compressed VRML world” means you should process the file as gzip before anything else, after which you’ll normally get a .WRL suitable for VRML/X3D viewers or older tools supporting VRML, and a reliable clue is the presence of gzip’s magic bytes 1F 8B at the start, which confirms it’s truly a gzipped VRML world rather than an unrelated format with a similar extension style.
Exploring a VRML “world” (the .WRL you get from unpacking a .WRZ) shows a scene graph of typed nodes describing visuals and user movement, with Transform/Group constructs managing transform hierarchies, Shape nodes merging geometry such as Sphere with Material/ImageTexture appearance, and standard world components including Viewpoint cameras, NavigationInfo behavior settings, and bindable environment nodes like Background, optional Fog, and Sound.
Here is more on WRZ file application look at the website. VRML’s interactivity uses Sensor nodes like ProximitySensor to send events, animations build on TimeSensor plus the Position/Orientation/Color/Scalar interpolators that provide time-based outputs, and ROUTE links connect everything, while complex behaviors rely on Script nodes with VRMLScript/JavaScript or occasional Java, and Anchor nodes allow hyperlink-like navigation, with the specification distinguishing transform-affected nodes from non-spatial ones such as interpolators, NavigationInfo, TimeSensor, and Script, giving the world the character of a small interactive program rather than a simple 3D model.
Saying a .WRZ is a “Compressed VRML World” means it isn’t a different format at all but a normal VRML world (.WRL) that’s been reduced with gzip to save bandwidth in VRML’s early web era, so the internal content remains VRML text defining geometry, textures, cameras, lights, navigation rules, and basic interactivity, wrapped in gzip and named .wrz or .wrl.gz—a practice documented by the Library of Congress—so decompression tools like 7-Zip/gzip work, and seeing the gzip magic bytes the hex header 1F 8B strongly suggests it’s genuine gzipped VRML.