Coursera

Coursera is a venture-backed, for-profit, educational technology company that works with universities and other organizations to make some of their courses available online.

Subjects offered include physics, engineering, humanities, medicine, biology, social sciences, mathematics, business, computer science, digital marketing, data science, and a number of others.

Each course includes short video lectures on different topics and assignments to be submitted, usually on a weekly basis and last approximately four to ten weeks, with one to two hours of video lectures a week.  These courses provide quizzes, weekly exercises, peer-graded assignments, and sometimes a final project or exam.  Courses are also provided on-demand, in which case users can take their time in completing the course with all of the material available at once.

Coursera offers a mobile app for iOS and Android operating-systems.