Then "AMZN.WEB-DL.x264". Let's take this part by part. "AMZN" could stand for Amazon, so this might be a release related to Amazon's website or their streaming service. "WEB-DL" usually means that the file was downloaded from a website that uses Dynamic Streaming or similar tech, which is different from a standard DVD rip. It's a way of getting a video directly from a streaming source rather than from a physical media. "x264" is the video codec used for encoding the video. It's a widely used open-source encoder for H.264/MPEG-4 AVC video compression. So, using x264 suggests that the video is compressed using this efficient codec, which is known for balancing quality and file size.