Question: I am flying from Tokyo to Paris, and I'm confused about daylight saving time. Is this a worldwide policy? Should I set my clock ahead one hour in Tokyo, the way I would in Los Angeles?
_Mark Watters, Simi Valley, Calif.
Answer: In answer to Watters' questions, no and no _ no, the whole world doesn't use daylight saving, and no, you should not move your clock by an hour.
But in answer to musical questions posed by the pop-rock group Chicago, "Does anybody really know what time it is? Does anybody really care?" Yes and yes. Several travelers have made suggestions on how to cope with timetable turmoil.
Let's see if we can get this sorted out.
IN THE DAYLIGHT
The U.S. begins daylight saving time this year on March 12 and ends it Nov. 5, according to the U.S. Naval Observatory, whose chart (www.lat.ms/navalchart) shows the dates we'll be changing through 2025 unless we decide to chuck the whole thing, which we have a few times.
Our country made standardized time zones the law in 1918, the observatory notes in its "History of Daylight Time in the U.S."
The 1918 Standard Time Act also included daylight saving time. At least it did until 1919, when it was repealed.
Local governmental entities got to choose whether to implement daylight saving, but in 1942, the U.S. mandated the spring-ahead, fall-back way of life for all.
That ended in 1945, and time became a hodgepodge of local desires.
Jump to 1966 and the Uniform Time Act, which established "uniform Daylight Saving Time throughout the nation and its possessions," according to the Department of Transportation.
"Uniform" is a bit of a misnomer. Hawaii, American Samoa, Guam, Puerto Rico, the U.S. Virgin Islands and parts of Arizona don't observe daylight saving time, according to DOT.
Confused? Carry on, and we promise you will be more so.
"Most of Europe observes daylight saving time, called 'summer time,'" Jeanna Bryner writes in "Daylight Saving Time 2017: A Guide to the When, Why, What and How" on LiveScience.com.
Europe begins its one-hour shift the last Sunday in March (March 26 this year) and ends it the last Sunday of October (Oct. 29).
But about 60 percent of the rest of the world isn't on daylight saving time, according to Timeanddate.com.
Japan started using daylight saving in 1948 but stopped in 1951, the site said, adding "Tokyo currently observes Japan Standard Time (JST) all year."
If you're traveling between Tokyo and Paris, the calculation on time is easy.
"The difference between Paris and Tokyo is eight hours before March 26 and seven hours after March 26," said Wojciech Borkowski of FlightFox.com, an online travel concierge and a lecturer at Frequent Traveler University, which teaches travelers to travel economically and efficiently.
Japan has only one time zone, Marian Goldberg, a travel marketing consultant and Japan travel planner, said in an email.
FIGURING IT OUT
How do you know what time it is?
Lauren Ball is owner and operator of TheHolidayGirl.com, an L.A. travel agency for millennial women.
In her spare time, she is a background vocalist for Katy Perry and has 67 countries on her travel resume.
Her suggestion: "All international travel is calculated on the GMT/UTC system, which is essentially like the equator but for time," she said in an email.
"All cities have a time assigned to this system and are either ahead or behind.
"Time zones are shown as plus/minus GMT/UTC (Greenwich Mean Time/Universal Time Coordinated) ... It's worth memorizing how many hours your hometown is from GMT/UTC, depending on the time of the year. Los Angeles is between eight or nine hours behind GMT/UTC."
You can find your time zone at WhatIsMyTimeZone.com, among other sites.
Ball also may wear an inexpensive wristwatch (rather than exposing a cellphone) that she sets to GMT/UTC time, making sure she knows how far ahead or behind her destination or home is.
Other travelers suggest using Timeanddate.com.
And then there is your smartphone. If you have an international cellular plan, it will adjust to your new location. (If you're in airplane mode and using Wi-Fi, Goldberg noted, it will not.)
Afrodite Pastroumas, a senior director product for TCS World Travel, a private jet tour operator, enters various cities she's traveling to or tracking in her phone's world clock function.
Kathy Cheng, founder of ThankfulRegistry.com, a gift registry that helps with baby or wedding gifts, is based in Taipei but works with people in various time zones.
She uses the phone too, but she said, "If I'm second-guessing myself, I literally Google 'What's the time in Tokyo?' and let Google enlighten me."
That is all, because we are out of time.
