At 2 a.m. on April 2, groggy Americans will turn their clocks forward one hour, marking the beginning of Daylight Saving Time (DST).

The federal law that established "daylight time" in this country does not require any area to observe daylight saving time. But if a state chooses to observe DST, it must follow the starting and ending dates set by the law. From 1986 to 2006 this has been the first Sunday in April to the last Sunday in October, but starting in 2007, it will be observed from the second Sunday in March to the first Sunday in November, adding about a month to daylight saving time

The Dawning of DST in Indiana Until April 2005, when Indiana passed a law agreeing to observe daylight saving time, the Hoosier state had its own unique and complex time system. Not only is the state split between two time zones, but until recently, only some parts of the state observed daylight saving time while the majority did not.

Under the old system, 77 of the state's 92 counties were in the Eastern Time Zone but did not change to daylight time in April. Instead they remained on standard time all year. That is, except for two counties near Cincinnati, Ohio, and Louisville, Ky., which did use daylight time.

But the counties in the northwest corner of the state (near Chicago) and the southwestern tip (near Evansville), which are in the Central Time Zone, used both standard and daylight time.

The battle between the old system and DST was contentious and hard-won—bills proposing DST had failed more than two dozen times in the past until it squeaked through the state legislature in April 2005. The old, familiar, bewildering system will remain in place for 2005; Indiana will join 47 other states in observing DST in April 2006.

New Federal Law—Springing Forward in March, Back in November But just months after Indiana got in step with the rest of the country, the federal government announced a major change in Daylight Saving Time. In Aug. 2005, Congress passed an energy bill that included extending Daylight Saving Time by about a month. Beginning in 2007, DST will start the second Sunday of March and end on the first Sunday of November.

Other Useful Tips: Every six months, officials recommend people to test their smoke detectors and carbon monoxide detectors. They said it is best to change the batteries in each of them every six months.