One iconic example: (QTVR). It wasn’t a codec but a media handler extension that allowed panoramic and object movies. Users could click and drag to look around a 360° room or rotate a 3D product on screen. For years, real estate and museum websites used QTVR—all powered by a 200 KB extension.
For modern systems, tools like ffprobe (from FFmpeg) can identify the FourCC or component type of a track. Example: quicktime extension
Today’s media pipelines (AVFoundation, Media Foundation, GStreamer) are more secure and performant, but they are also more rigid. Installing a new codec on an iPhone requires an app update and Apple’s approval. In 1997, you just dropped a file into a folder. One iconic example: (QTVR)