They're not only for daylight saving time
They're for local (and national) convenience – it's not often most people need to add (or subtract) timezones
Why make them math if you don't need to?
August 30, 2020 at 02:13PM
via reddit https://www.reddit.com/r/explainlikeimfive/comments/ijgmvi/eli5_is_there_a_specific_use_for_stating_pdt_pst/g3dp2f4?utm_source=ifttt