What is glTF you ask? It’s a file format for 3D models — and it is cool! It was created by the Khronos Group, who are the same folks responsible for OpenGL, and it is glorious. First, it contains all the data you need: scenes, lights, cameras, geometry, materials, animations, & morph targets. Second, it’s open, well-documented, and straight-forward. Third, it has both binary & text formats, and the text-format is JSON. Fourth, did I mention the text format is JSON? Oh, how I love JSON!
I suppose you may have to implement other 3D format readers to truly appreciate it (DXF anyone?), but it is slick. For any programmer implementing a 3D model reader who is trying to decide between OBJ, DXF, Collada, et al., the answer is glTF! Trust me on this one.