Vertical Sync, or VSync, synchronizes the revive rate and casing pace of a screen to forestall screen tearing. VSync does this by restricting your GPU's casing rate result to your screen's revive rate. The GPU then utilizes extravagant specialized stunts like page flipping and twofold buffering to show outlines after a screen's revive cycle closes, so you don't see tearing regarding what is vsync.
VSync is very important for your PC and big companies like Nvidia and AMD have made their own refresh rate technologies based upon the vsync. If your graphics card supports the feature you can turn on vsync on your monitor.