controls

Specifies that audio controls should be displayed (such as a play/pause button, etc.)

<audio controls>
    <source src="http://www.sololearn.com/uploads/audio.mp3" type="audio/mpeg">
    Audio element not supported by your browser. 
</audio>

autoplay

When this attribute is defined, audio starts playing as soon as it is ready, without asking for the visitor's permission

<audio controls autoplay>
    <source src="http://www.sololearn.com/uploads/audio.mp3" type="audio/mpeg">
    Audio element not supported by your browser. 
</audio>

loop

This attribute is used to have the audio replay every time it is finished

<audio controls autoplay loop>
    <source src="http://www.sololearn.com/uploads/audio.mp3" type="audio/mpeg">
    Audio element not supported by your browser. 
</audio>