Linus Torvalds said of this issue:

"As to the whole 'hybrid kernel' thing - it's just marketing. It's 'oh, those microkernels had good PR, how can we try to get good PR for our working kernel? Oh, I know, let's use a cool name and try to imply that it has all the PR advantages that that other system has'."

In 2007, I met Philip Wadler at a conference, who mentioned to me that he wanted to teach lambda calculus to his eight-year-old children.