A prior post started a simple acronym FUSE to describe glTF. 

Here let's double click on the first letter F, which stands for Fast. 

Typically, exporting a glTF from xStudio only takes minutes in the background. You can keep running xStudio without any interruption. The finished export will automatically arrive in your system notification. 

On the consumption side, speed stands front and center of any user experiences. It has been a challenge in the past decades with 3D on webpages.

Now this barrier gets remarkably lowered. Loading a webpage with 3D has become much faster. You may try examples for the first-hand insights, such as this Jigsaw page, which shows up in merely seconds, even on mobile devices with cellular networks. 

One step further, why does glTF run so fast? The key measure is to simplify and compress. 

As shown below, first, glTF is not an authoring format. It removes any design information such as native features, component constraints, metadata and so on, which not only desensitizes data to address security concerns, but also cuts down file sizes significantly. 

Additionally, default and optional compressions get applied to both Geometries and Textures. 

For example, you may notice the optional Geometry Compression on the glTF Export dialog in xStudio .

If we turn it on, this drone glTF shrinks from 7.5MB to only 1.1MB. 

However, please remember to verify your glTF viewer, because not all support the optional geometry compression yet. For instance, if we open the attached 1.1MB glTF in the Khronos viewer, you may run into an error message below. 

As to texture compressions, a prior post shared a bit more. 

That's it for "Fast" for now. Next, we'll move on to Universal, in FUSE (Fast, Universal, Simple, Engaging)😃.