American and Canadian railroads institute five standard continental <a href="https://en.wikipedia.org/wiki/Time_zone" id="mwpA" rel="mw:WikiLink" title="Time zone">time zones</a>, ending the confusion of thousands of <a href="https://en.wikipedia.org/wiki/Time_in_the_United_States#History" id="mwpQ" rel="mw:WikiLink" title="Time in the United States">local times</a>.