Internet time is a phrase that has at least two possible meanings. The most common is a system devised by a watch company that divides the day into 1000 units and attempts to remove the concept of time zones. The phrase can also refer to the Coordinated Universal Time system.
The most prominent version of Internet time was a proposal by Swiss watch making company Swatch. While presented as a serious concept, it was seen by many as a marketing stunt. No official organizations have adopted the system, though it was used as the official time system of an online "virtual country" designed for and used by children.
Swatch's Internet time system has three main differences to normal time systems. The most prominent is that instead of using hours, minutes, and seconds, it simply divides the day into 1000 equal units known as beats. Each beat lasted for one minute and 26.4 seconds in standard time. The time was displayed as a three digit number preceded by the @ sign. For example, 6 p.m. in standard time would be listed as @750 in Swatch's system.
The other major change with Swatch's Internet time system was that it did not recognize time zones. Instead, every user in the world would recognize the same time. This would require local adjustments as, for example, @500 would be the middle of the day on one side of the world and the middle of the night elsewhere.
The Swatch system also used a different meridian to most time systems, with the line not-so-coincidentally passing through the company's office in Biel, Switzerland rather than the traditional meridian of Greenwich, England. This meant that @500 would mark the high point of the sun passing overhead in Biel, and the equivalent of one hour before this happened in Greenwich.
Internet time can also refer to Coordinated Universal Time, known as UTC. This is the time system used by many computer systems, and is often used to avoid confusion over systems operating in different time zones. UTC matches up with Greenwich Mean Time, meaning that noon in UTC happens at the same time as noon in GMT, 7 a.m. in New York and 4 a.m. in Los Angeles. The two are different in technical terms though: UTC is maintained with a leap second system, by which an extra second may be added at the end of June or December to make up for the fact that the Earth's rotation is gradually slowing down.