Summary

Until now, you may have felt that the world of time management was simple. A day has 24 hours, and a year consists of 365 days. In this chapter, we have shown that there is 1 day of the year that has only 23 hours and one that has 25 hours because of the transition to summer and winter time, described as DST. Similarly, although a standard year is made up of 365 days, there is also a leap year in which there is 1 extra day. The difference between the Julian and Gregorian calendars and the related leap year occurrence was also discussed.

Time zones are an integral part of the calendar and time. In the past, information systems were only local – server and client time were always the same. The client and server were in the same time zone within one small geographical area. With the globalization of systems, markets, and businesses, it is necessary to pay attention to time zones and transitions between them. We have described the concept of UTC, which is used for time...