What is an OGV file?

Could you please explain to me what an OGV file is? I've come across this term in the context of video files, but I'm not entirely sure what it stands for or what its purpose is. Is it a specific type of video format? How does it differ from other video file formats like MP4 or AVI? And what kind of software or devices are typically used to play OGV files? I'd appreciate any clarification you can provide on this topic.