Hi,
Its customary to use a code that will tell HTML5 to use various video formats, so users with different systems will see the video using the version suitable for them. Then you create / store your video in various formats such as ogg, mp4, webm etc.
Check this example:
<!DOCTYPE html>
<!-- video.html by Bill Weinman https://bw.org/ -->
<html lang="en">
<head>
<meta charset="UTF-8" />
<title>
HTML5 Video
</title>
<script>
var video;
function init() {
video = document.getElementById('video1');
}
function play() { video.play(); }
function pause() { video.pause(); }
function rewind() { video.currentTime = 0; }
window.onload = init;
</script>
</head>
<body>
<h1>
HTML5 Video
</h1>
<p> Here's a video: </p>
<video id="video1" width="860" height="480" controls>
<source src="media/video.m4v" type="video/mp4" />
<source src="media/video.webm" type="video/webm" />
<source src="media/video.ogg" type="video/ogg" />
<p> Your browser does not support the HTML5 video feature. </p>
</video>
<form>
<input type="button" value="Play" onclick="play()" />
<input type="button" value="Pause" onclick="pause()" />
<input type="button" value="Rewind" onclick="rewind()" />
</form>
</body>
</html>