A .WRZ file is most commonly understood as 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 reduced in size 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 decompress 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 simple check is seeing whether the file begins with 1F 8B, which is typical of gzip-compressed data and supports the idea that WRZ is a gzipped WRL, and people often mix it up with RWZ, a format associated with email rule exports, so a file from an email setup is probably RWZ, while one from a 3D workflow is almost certainly WRZ.
A .WRZ being called a "Compressed VRML World" means the file is just a VRML world—commonly stored as .WRL, where the extension means *world*—that’s been
gzip-compressed for easier storage or earlier web transfer, as VRML’s text-based scene description (objects, textures, lighting, cameras, and sometimes animations) compresses extremely well, resulting in conventions like naming such files .wrl. Here is more information on
WRZ file support check out our own site. gz or .wrz.
In practical terms, "compressed VRML world" also tells you exactly how to handle it: treat the file as a gzip stream first, which will usually yield a .WRL you can load in VRML/X3D viewers or import into tools that still understand VRML, and a simple technical hint is the gzip "magic bytes" 1F 8B, which, if present at the start of the WRZ in a hex viewer, strongly suggests it’s a genuine gzipped VRML world rather than some unrelated format with a similar extension.
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 various hit-test sensors 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.
What "Compressed VRML World" means for a .WRZ file is that WRZ isn’t its own 3D format but simply a regular VRML scene file—usually .WRL—packed via gzip to reduce size back when web bandwidth was tight, so the content is still VRML text describing shapes, lights, textures, viewpoints, navigation, and simple interactivity, just stored inside gzip and labeled .wrz or .wrl.gz, a convention noted by sources like the Library of Congress, which is why tools like 7-Zip/gzip open it and why checking for the gzip signature 1F 8B helps confirm it’s truly gzipped VRML.