TIMEZONEINFORMATION

TIMEZONEINFORMATION is a structure used in Windows operating systems to store information about a specific time zone. This structure is fundamental for handling date and time calculations accurately across different geographical regions. It contains details such as the standard and daylight saving time names, the bias from Coordinated Universal Time (UTC), and rules for when daylight saving time begins and ends.

The TIMEZONEINFORMATION structure includes members like StandardName, DaylightName, StandardDate, and DaylightDate. The StandardName and DaylightName members are wide character strings that hold the names of the standard and daylight saving time periods, respectively. The StandardDate and DaylightDate members are SYSTEMTIME structures that specify the date and time when the standard time and daylight saving time come into effect each year.

Furthermore, the Bias member represents the difference, in minutes, between UTC and local time. This bias can change when daylight saving time is in effect. The DaylightBias member specifies the additional offset, in minutes, that is added to the Bias when daylight saving time is active. The TimeZoneKeyName member stores the registry key name for the time zone, which is useful for uniquely identifying a time zone.

Applications utilize the TIMEZONEINFORMATION structure to retrieve and set time zone parameters, enabling them to display local time correctly for users in various parts of the world. This structure is a key component in the Windows Time Service and other date/time-related APIs, ensuring consistency and accuracy in timekeeping.