According to this site, Zen is the original teaching of the Buddha, and the other Buddhist schools are just "dogmatic religions": http://www.zen-buddhism.net/faq/zen-faq.html
What Are The Differences Between Zen And Buddhism?
"Around five centuries after the Buddha passed away, Buddhism traveled to various Asian countries where it got transformed into a dogmatic religion with rituals and ceremony, departing from its true origins. Zen stayed true to the original teaching of the Buddha which lays emphasis on Zazen, and not on rituals and theoretical concepts."
But hang on a minute. Buddhism arrived first in China ( one of the "Asian countries" ) where it mingled with Taoism and became known as Chan, then later it migrated to Japan and adapted to Japanese culture, becoming known as "Zen".
So how can they imply that only Zen stayed true to the original teaching of the Buddha, and claim that all the other Buddhist schools are merely "dogmatic religions"? To me it sounds nonsensical, just self-promoting rhetoric. I get the point about a focus on meditation, but that isn't exclusive to Zen.