The tz database is a collaborative compilation of information about the world's time zones and rules for observing daylight saving time, primarily intended for use with computer programs and operating systems.[2] Paul Eggert has been its editor and maintainer since 2005,[3] with the organizational backing of ICANN.[4] The tz database is also known as tzdata, the zoneinfo database or the IANA time zone database (after the Internet Assigned Numbers Authority), and occasionally as the Olson database, referring to the founding contributor, Arthur David Olson.[5]
Its uniform naming convention for entries in the database, such as America/New_York and Europe/Paris, was designed by Paul Eggert.[6] The database attempts to record historical time zones and all civil changes since 1970, the Unix time epoch.[7] It also records leap seconds.[8]
The database, as well as some reference source code, is in the public domain.[9] New editions of the database and code are published as changes warrant, usually several times per year.[10]
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