Comment by irrational

Jquery became popular because at the time there were all these browsers and none of them did things the same. They weren’t standards compliant like most browsers are today. So you ended up writing a ton of code and css that basically said, “if browser x - do this - else if browser y - do this”. Then jQuery came along and took care of all of that for you. They made it so you could just write for jquery and it would take care of translating it into what browser the person viewing the site was using. It made things so much easier. jQuery was basically write once, run everywhere, for the browsers of those days.