Victor Bastos, 36, used to be a freelance Web developer in Lisbon, Portugal. A few years ago, he started posting tutorial videos about computer programming on YouTube, and people found them useful and inspiring. That was when Udemy, an online teaching and learning platform based in Silicon Valley, called him and offered to host his video lectures. In exchange, Udemy would take 30 percent of the tuition that Bastos charged students, which was $49 (308 yuan) per course at first, a price that was later *bumped up to $199.