Gilbert Strang, an MIT professor, taught the same linear algebra course for 62 years. When he delivered his final lecture in May 2023, students from around the world tuned in online to watch. The course is MIT 18.06 Linear Algebra. Millions of machine learning engineers, data scientists, quants, and self-taught programmers learned the essential math behind AI from his clear, free video lectures, even though most never stepped foot on the MIT campus. Strang joined the MIT faculty in 1962 and retired in 2023. When MIT launched OpenCourseWare in 2001–2002, he was one of the first to embrace it fully. While many professors hesitated, Strang saw it as an opportunity to share mathematics with everyone. He filmed his lectures and made them freely available. He completely changed how linear algebra is taught. Instead of starting with abstract vector spaces and proofs, Strang began with something simple and visual: matrix multiplication. He built intuition first using concrete examples, then introduced more advanced ideas like eigenvectors and singular value decomposition. He insisted that students should be able to explain every concept with a small, tangible matrix before moving to theory. Beyond the content, his teaching style stood out. He spoke to students with genuine respect, patience, and kindness, never using words like “obviously” or “trivially.” He regularly paused to check if anyone was lost and treated beginners as thoughtfully as he would his colleagues. As a result, Strang became the default linear algebra teacher for much of the planet. Universities in many countries began recommending his lectures to their own students. Some even replaced their in-person courses with his videos because they could not match their clarity. His final lecture ended with a long standing ovation. Strang seemed surprised by the applause, smiled humbly, and simply thanked everyone. In his short comment under the YouTube video, he expressed gratitude for a wonderful life of teaching and hoped others would continue teaching the subject well. No self-promotion, no grand farewell—just quiet sincerity. When you add up every version, every upload, help sessions, and all the different recordings MIT has shared over the years, the total has surpassed 20 million views. Today, the full course, including all lectures, problem sets, and solutions, remains freely available on MIT OpenCourseWare. One of the most important mathematical foundations of modern AI is still just one click away.