Jank Busting for Better Rendering Performance - HTML5 Rocks: "INTRODUCING V-SYNC
PC gamers might be familiar with this term, but it's uncommon on the web: what is v-sync?
Consider your phone's display: it refreshes on a regular interval, usually (but not always!) about 60 times a second. V-sync (or vertical synchronization) refers to the practice of generating new frames only between screen refreshes. You might think of this like a race condition between the process that writes data into the screen buffer and the operating system reading that data to put it on the display. We want the buffered frame contents to change in between these refreshes, not during them; otherwise the monitor will display half of one frame and half of another, leading to "tearing"."
'via Blog this'
