Check out example codes for "html5 iframe youtube loop". It will help you in understanding the concepts better.

Code Example 1

<iframe class="embed-responsive-item"id="ytplayer" type="text/html" width="640" height="360" src="https://www.youtube.com/embed/M7lc1UVf-VE?&autoplay=1&loop=1&rel=0&showinfo=0&color=white&iv_load_policy=3&playlist=M7lc1UVf-VE"
      frameborder="0" allowfullscreen></iframe>

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