A .WRZ file is basically a gzip-compressed VRML scene, where a .WRL world file—containing text-based 3D data such as shapes, materials, lights, cameras, and occasional animations—has been compressed because VRML compresses extremely well, leading to the convention of naming these archives .WRZ or `.wrl.gz`, and the usual method of opening them is to unzip with something like 7-Zip or `gzip` to produce a .WRL that VRML/X3D tools can read, provided any texture images remain in the correct relative paths.
A quick way to verify a real gzip file is to check whether it starts with the signature bytes the hex pattern 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 email filtering rule files 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 reduced using gzip 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. If you have any concerns regarding where and how you can use WRZ file reader, you could call us at our website. gz or .wrz to indicate a gzipped VRML world.
From a practical standpoint, the phrase “compressed VRML world” signals that you should open the file as a gzip archive first to recover a .WRL usable in VRML/X3D-capable software, and you can verify this by checking for gzip’s magic bytes 1F 8B in a hex viewer, which is strong evidence you’re dealing with an authentic gzipped VRML file, not a look-alike format.
Inside the VRML “world” (the .WRL produced after you decompress a .WRZ) you’ll find a typed scene graph covering both scene content and navigation, starting with Transform/Group nodes that define position, rotation, and scale, then Shape nodes that mix geometry—IndexedFaceSet—with appearance through Material and ImageTexture, as well as world-level nodes like Viewpoint, NavigationInfo, Background, Fog, or Sound.
Interactivity in a VRML world is handled through Sensor nodes like ProximitySensor that emit events, while animation is driven by TimeSensor plus Position/Orientation/Color/Scalar interpolator nodes that output changing values over time, all connected using ROUTE links (eventOut → eventIn), and more complex behavior comes from Script nodes using VRMLScript/JavaScript or sometimes Java, along with Anchor nodes for hyperlink-style jumps, with the spec separating transformable nodes in the hierarchy from non-spatial nodes like interpolators, NavigationInfo, TimeSensor, and Script, which is why a VRML world behaves like a small interactive program rather than a simple mesh.
Calling a .WRZ a “Compressed VRML World” means the file isn’t a unique format but a standard VRML world (.WRL) compressed with gzip to shrink download/storage size from the early web-3D period, leaving the VRML text intact—shapes, textures, lights, viewpoints, navigation, and simple behaviors—just packaged in gzip and signaled with .wrz or .wrl.gz, as noted by references like the Library of Congress, which is why 7-Zip/gzip opens it and why identifying the gzip 1F 8B bytes helps confirm it’s really gzipped VRML.