Video Upload at server

Question

I am new in coding . i haven't any idea about video tag. Please help me. 

 

<video id="youtube_video" autoplay controls>

<source src="img/VID-20161017-WA0019.mp4" type="video/mp4" />

</video>

 

this is my code lines . its run properly at local server but when i hosted it at server , video is not running.  

 

thanks.