The funniest result i saw was telling me the local time in Millis, Massachusetts. There was nothing like it in the search results. Since a program was already running, rather than just inspecting Java's System.currentTimeMillis() or running a program that shows it to me, i figured i'll open a web page that shows it. Why 1970 you ask? It's just a convention: it was the roundest most recent year to the point in time people actually started thinking about a universal measure of time.Īs i was debugging i needed something to tell me what the current time in ms is. This number has to be so large that it can encompass all the time passed since midnight January 1st, 1970 but sufficiently small that it can fit into existing data structures and keep going enough time in the future. In Android you tell an alarm when to come up by passing a simple number. The "current millis" story started with me debugging my Android application. More importantly, this site offers a time navigation service for human users and a time authority service for programmatic usage. You can also convert milliseconds to date & time and the other way around. This site provides the current time in milliseconds elapsed since the UNIX epoch (Jan 1, 1970) as well as in other common formats including local / UTC time comparisons. From this point of view the name “GMT” seems deprecated, but kept around for backward compatibility, traditional timezone based representation of time and sometimes legal reasons. If you were to calculate true GMT today i would see it based on its original definition of 1 second = 1/86400 days and this would for sure return a different absolute value than what UTC gives us. These 2 turning points (different definition of a second and the introduction of leap seconds) ‘forced’ GMT to be the same as UTC based on what seemed a gradual, tacit convention. In 1972 leap seconds were introduced to synchronize UTC time with solar time. UTC’s second is far more precise than GMT's original second. Unlike GMT which is based on solar time and originally calculated a second as a fraction of the time it takes for the Earth to make a full rotation around its axis, UTC calculates a second as “the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom”. UTC essentially appeared in 1960, GMT being the ‘main thing’ until then. Resulting erroneous calculations on such systems are likely to cause problems for users and other reliant parties.Literature and history are a bit ambiguous. This reports a maximally negative number, and continues to count up, towards zero, and then up through the positive integers again. This is caused by integer overflow, during which the counter runs out of usable digit bits, and flips the sign bit instead. Programs that attempt to increment the time beyond this date will cause the value to be stored internally as a negative number, which these systems will interpret as having occurred at 20:45:52 on Friday, 13 December 1901 (2,147,483,648 seconds before 1 January 1970) rather than 19 January 2038. The latest time since 1 January 1970 that can be stored using a signed 32-bit integer is 03:14:07 on Tuesday, 19 January 2038 (231-1 = 2,147,483,647 seconds after 1 January 1970). Similar to the Y2K problem, the Year 2038 problem is caused by insufficient capacity used to represent time. Such implementations cannot encode times after 03:14:07 UTC on 19 January 2038. The Year 2038 problem (also called Y2038, Epochalypse, Y2k38, or Unix Y2K) relates to representing time in many digital systems as the number of seconds passed since 00:00:00 UTC on 1 January 1970 and storing it as a signed 32-bit integer. Due to this treatment Unix time is not a true representation of UTC. It is the number of seconds that have elapsed since the Unix epoch, minus leap seconds the Unix epoch is 00:00:00 UTC on 1 January 1970 (an arbitrary date) leap seconds are ignored,with a leap second having the same Unix time as the second before it, and every day is treated as if it contains exactly 86400 seconds. Unix time (also known as Epoch time, POSIX time,seconds since the Epoch,or UNIX Epoch time) is a system for describing a point in time. Seconds Convert Human date to Timestamp → Unix Timestamp
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