The number of times a second that the screen refreshes its image is known as refresh rate. A high refresh rate allows busy content, including live sports and online video games, to avoid blurring, lagging or shadowing on screen. Especially for gamers who play competitively in online environments, a high refresh rate is important. Gamers tend to prefer a minimum of 144Hz, but higher-end Dell Alienware options offer up to 360 Hz refresh rate. Respond speed is measured in milliseconds; most gamers seek out at least a 3ms response time, while 1ms is the best offered.