MOOCs are massive open online courses that make educational content widely available over the internet without cost. They allow for lifelong learning and can be taken by anyone. While MOOCs increase access to education, they also present challenges like making discussion difficult and increasing dropout rates. However, they are free for students and help address issues like overcrowded classrooms. MOOCs have evolved from early open educational resources and radio-based learning from the early 20th century. They are typically connectivist, focused on networking, or instructivist, focused on guided content and assessment.