Time

Time is all about the synchronization. We monitor the time to synchronize our behavior: with others - to meet, with the events - to attend, and even with ourselves - to keep up our own wellness in the good state. Since nobody has the reliable sense of time we need some kind of the "time agents", for example, the clocks to meet with others or the software to monitor the wellness.

To successfully synchronize the people, their clocks should show the same time. However people also would like to synchronize their life with the sunrise and sundown. Since, for example, the sunrises in different parts of the globe may be up to 12 hours apart we actually need at least two types of clocks. The first type that is often called "wall clock" is to know our local time and the second type that is often called "world clock" is to know the universal time that by definition is the same in any world time zone.

According to the standard, the universal time is actually the local time in the Greenwich (a place in Greater London, England). It is called UTC (Coordinated Universal Time). Earlier standard defined the slightly different time called GMT (Greenwich Mean Time). The difference between UTC and GMT is less than one second and in most case may be neglected.

World time (UTC or GMT) is perfect to avoid the ambiguities in the time synchronization between different time zones but it is useful rather in the recording of already negotiated time for the future meeting, conversation or other event. To initiate the communication we need to know the local time of our partners, to figure out, for example, should we call to the office or home. It means that we often should know the time shifts between our local time and the local times of our partners. Unfortunately, the time shifts are prone to errors because they change their value at the moment of the daylight saving time and this moment is different in different time zones and even countries.

We see that the time shifts between particular time zones or geographical locations are good to initiate the long distance scheduling, however the scheduled time is better to record in the world time units i.e. in UTC or GMT.