WeBWorK was started about 1996 by two University of Rochester Mathematics professors, Mike Gage and Arnie Pizer. It had its seeds in the CAPA system for Physics homework. As of June 2020, there are more than 1300 institutions using WeBWorK world-wide
From the WeBWorK Wiki
WeBWorK is a well-tested homework system for delivering individualized problems over the web. By providing students with immediate feedback as to the correctness of their answers, students can be encouraged to make multiple attempts until they succeed. With individualized problem sets, students can work together but will have to enter their own work to receive credit.
The instructors are provided with real-time statistics, resulting in lesson plans that can be customized to better serve students. As of June 2020 there were more than 1300 institutions using WeBWorK and the Open Problem library now has over 35,000 curated and indexed exercises. The majority of the institutions using this homework system are located in the USA, but many are located in Canada and Mexico, as well as in Europe, Asia, and Africa.