Do mp4 only have songs

No, MP4 files do not only contain songs; they are versatile multimedia containers that can hold various types of data, including audio, video, and subtitles. While many MP4 files are used for music and audio tracks, they can also store video content, making them suitable for movies, podcasts, and other multimedia presentations. This flexibility is one of the reasons why MP4 has become a popular format for digital media.