Edit in JSFiddle

<video width="480" controls
  poster="https://archive.org/download/WebmVp8Vorbis/webmvp8.gif" >
  <source
    src="https://archive.org/download/WebmVp8Vorbis/webmvp8.webm"
    type="video/webm">
  <source
    src="https://archive.org/download/WebmVp8Vorbis/webmvp8_512kb.mp4"
    type="video/mp4">
  <source
    src="https://archive.org/download/WebmVp8Vorbis/webmvp8.ogv"
    type="video/ogg">
  Your browser doesn't support HTML5 video tag.
</video>