Here are 23 ways to learn Docker for free:

  1. Runnable, Slash Docker — Blog.
  2. Docker, Docker 101 Tutorial — Blog.
  3. Online IT Guru, Docker Tutorial — Blog.
  4. Tutorials Point, Docker Tutorial — Blog.
  5. Andrew Odewahn, Docker Jumpstart — Blog.
  6. Container (dot) Training — Blog and Videos.
  7. Romin Irani, Docker Tutorial Series — Blog.
  8. LearnDocker (dot) Online — Blog And Videos.
  9. Noureddin Sadawi, Docker Training — Videos.
  10. Code Review Videos, Docker Tutorial — Videos.
  11. Learn2torials, Latest Docker Tutorials — Blog.
  12. Docker Curriculum, Docker For Beginners — Blog.
  13. Programming With Mosh, Docker Tutorial — Video.
  14. Jake Wright, Learn Docker In 12 Minutes — Video.
  15. Digital Ocean, How To Install And Use Docker — Blog.
  16. LinuxTechLab, The Incomplete Guide To Docker — Blog.
  17. Play With Docker Classroom, Play With Docker — Blog.
  18. Shota Jolbordi, Introduction to Docker — Blog Series.
  19. Free Code Camp, Docker Tutorial For Beginners — Video.