What are these symbols called and what do they do?

[Loneranger2234]

When I am playing a video on my iPhone and I pause the video, I see this. What are these open circles with the arrow at one end? Are these refresh symbols? What do they do when you click on one? Thanks--

 

[strollin]

Left one rewinds a few seconds, right one fast forwards a few seconds.

 

[Loneranger2234]

Cool, thanks strollin.