History
Who invented time zones?
Standard time was not invented by one person. Railway planners, scientists and public institutions converged on a shared answer to a very practical problem.
Every town once kept its own time
Before standard time, local noon was set by the Sun. A town a little way east saw noon before a town west of it, so their clocks differed by minutes. That was manageable for local life and bewildering for a railway timetable.
Railways needed a timetable people could trust
In the United States, proposals by Charles F. Dowd, Sir Sandford Fleming and others helped shape a practical four-zone railway system. Railroad companies adopted Standard Railway Time on 18 November 1883, synchronising operations even before federal law later defined time-zone authority.
The invention was an agreement
Time zones are less like a patent and more like a public convention. The Sun provides longitude; transport, communication, governments and software decide which shared clock a place will use. That is why the system still changes when a government changes the rule.