Time change ruining your sleep? Simple ways to fall asleep faster
Every spring, when we advance our clocks, millions of people struggle to get enough sleep in the days ahead. Simple things can help.
LEARN MOREWhy does the U.S. not use military time?
In Ancient Egypt and Rome, the day and night were divided into 12 hours each.
Why does the U.S. not use military time?
Charles Krupa / AP
March 14, 2023
If you’re guilty of accidentally setting your alarm on your smartphone for 6 p.m. instead of 6 a.m. — you’re not alone.
Most Americans prefer the a.m.-p.m. system instead of the 24-hour clock.
But why? Historians believe Babylonians came up with the concept of the 12-hour clock. It’s believed they were inspired by the 12 lunar patterns and 12 zodiac signs in their annual calendar.
In Ancient Egypt and Rome, the day and night were divided into 12 hours each. To tell time, Egyptians used sundials during the day and water clocks at night.
Centuries later, the first faceless mechanical clock made out of iron came out of England in 1283. The 24-hour analog dial was soon invented and spread across Europe.
But as the years went by, clockmakers found the 12-hour analog simpler and cheaper. And in the 15th and 16th centuries it became the standard in northern Europe.
Still, the use of a conceptual 24-hour system has been popular in most of the world since the 19th century.
Airlines and public transit use 24-hour time to avoid confusion between a.m. and p.m. hours.
Yet over a dozen countries use the 12-hour clock almost exclusively, as the written and spoken system of time.
3:46
How are U.S. jobs reports compiled?
The data is based off estimates and not full official counts of the entire labor force, which is now over 160 million strong in the U.S.
4:15
Why are single women outnumbering single men in homeownership?
One big factor is that women’s earnings have steadily increased in the past decade.
2:30
Why are some citizens protesting in France?
Hundreds of people were arrested in clashes amid some the biggest protests so far against the raising of France's retirement age.
Top Stories
NBA, players reach deal for a new labor agreement
One part says players will have to appear in at least 65 games in order to be eligible for the top individual awards such as Most Valuable Player.
Pope Francis leaves hospital; 'Still alive,' he quips
In a sign of his improved health, the Vatican released details of Pope Francis' Holy Week schedule.
One dead, several injured in roof collapse at Illinois theater
Severe weather is to blame for the roof collapse during a heavy metal concert at the Apollo Theater in Belvidere, Illinois.
