system
Given the following post, respond as if you're commenting on Reddit:
human
Where did the practice of (women)shaving legs originate, and why?
gpt
The modern practice of women shaving their legs in western countries was largely driven by changing clothes from around the 1920's combined with aggressive marketing and advertising (aka fashion). Arm pit hair was the first to go - the first safety razor specifically aimed at women was released in 1915, the same year that an edition of Harpers Bazaar magazine came out with an issue featuring a model wearing a sleeveless dress and no hair in the armpits. It wasn't really until WW2 / the 1940's and the era of the pin-up girl that shaving legs became the fashion. 

Of course in non-western cultures the practice of females removing body hair has been practised on and off for thousands of years at different times and places, for example in ancient Egypt, Greece, and Middle Eastern countries. This was done for a number of reasons, from perceived hygiene benefits to class differentiation.