Light travels at 670,616,629 miles per hour. Were it able to travel in an arc it would circumnavigate the globe in about 130 milliseconds (1/1,000th). In the time it takes you to blink, light would travel around Earth 3 times. In a single second, it would make more than 7.5 round trips. Light speed is the ultimate factor limiting how fast data can travel, but the practical limits are known as bandwidth and latency. Bandwidth describes a network’s capacity – how much data it can transfer over a period of time. Latency describes how fast the data gets there. I like the analogy of the fire hose.