Daylight saving time 夏时制
(重定向自Day Light Saving Time)




Daylight saving time (DST) or summer time is the practice of advancing clocks during summer months by one hour so that evening daylight lasts an hour longer, while sacrificing normal sunrise times. Typically, regions with summer time adjust clocks forward one hour close to the start of spring and adjust them backward in the autumn to standard time. People use the terms" spring forward" and " fall back " when referring to this.