This tutorial teaches users how to use AssemblyAI to transcribe videos and automatically generate accurate subtitles in both SRT and VTT formats. It covers setting up the environment, choosing a subtitle format, transcribing the video file, generating subtitles, and customizing the output. The differences between SRT and VTT are also discussed, with SRT being suitable for traditional media players like VLC, while VTT is better suited for web browsers.