There are free courses as well as courses that are free to audit, which means you can take the course for free but there is a cost to upgrade for additional content and/or to receive a verified certificate from HarvardX.
Khan Academy is a non-profit educational organization created in 2006 with the aim of providing a free, world-class education for anyone, anywhere.
General Ronald Fogleman created the CSAF Professional Reading Program in 1996 to develop a common frame of reference among Air Force members — officers, enlisted, and civilians — to help each of us become better, more effective advocates of air and space power.
AF e-Learning offers upgrade training and continuing education resources to help active-duty, Reserve, Guard and Air Force civilian cyber professionals achieve their goals.
edX is a repository of course offerings by big name entities such as Harvard.
Build skills with courses, certificates, and degrees online from world-class universities and companies.
These certificate courses are designed to help educate and prepare enlisted leaders assigned to Joint organizations or those going to Joint assignments.
The Air Force Institute of Technology School of Systems and Logistics offers a wealth of various different course topics.
The FEMA Emergency Management Institute (EMI) offers self-paced courses designed for people who have emergency management responsibilities and the general public. All are offered free-of-charge to those who qualify for enrollment.
DAU is a modern learning platform delivering continuous learning and support tailored to the needs of the Defense Acquisition Workforce.