tl;dr: The two-day weekend turns 100 this year, having been popularized by Henry Ford in 1926 (and Boots in the UK in 1933) as a productivity and consumer-capitalism play — while a Soviet experiment with staggered days off from 1929-1940 failed because shared time off is what makes leisure meaningful. Today the weekend is fraying: remote "time owners" have quietly turned Friday into a half-day ("Skiveday Friday"), while shift workers remain clock-bound, and smartphones let work bleed into Saturday and Sunday. The four-day week is gaining traction, with 56 of 61 UK pilot companies sticking with it.