North American Central Time Zone

The Central Time Zone observes standard time by subtracting six hours from UTC during standard time (UTC−6) and five hours during daylight saving time (UTC−5). The clock time in this zone is based on the mean solar time of the 90th degree meridian west of the Greenwich Observatory. In the United States and Canada, this time zone is generically called Central Time (CT). Specifically, it is Central Standard Time (CST) when observing standard time (Winter), and Central Daylight Time (CDT) when observing daylight saving (Summer).The zone is one hour ahead of the Mountain Time Zone and one hour behind the Eastern Time Zone.
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