High-school-level courses on a number of subjects
Free courses in various languages, from French to Turkish via High Valyrian.
The Open University (UK) Free Courses
The Open University was founded in 1969 and its degrees are now widely recognised by employers. Some of these taster courses can result in certification.
MIT Open Courseware
Massachusetts Institute of Technology is one of the most famous educational institutions in the world and has made a lot of its course content available for free.
Open Yale Courses
Yale is another prestigious institution offering free courses.
Saylor.org is working to establish itself as a genuinely free university. It offers a range of high-quality, free courses.
Free online typing course
In my opinion, typing is one of the most useful skills anyone can learn.
Microsoft Office Support
Brush up your skills with Microsoft Office with help from the people who developed it.
Google Digital Garage
If you want to learn about the web, learn from the masters of it.
THE name in search engine optimization offers a huge range of free resources.
Free sales and marketing training.
Learn to code for free.
Microsoft Virtual Academy
This is for people who want to learn to create software in Microsoft environments.