The origin of Zen comes from greater vehicle Buddhism. In Buddhism, we have two main derivatives: greater vehicle Buddhism and small vehicle Buddhism.
Small vehicle Buddhism devotedly focuses on what Buddha done to reach nilvana. So, they execute tough ascetic training in shrines.
But, as we know, not everyone can execute such training because of many reasons. So, greater vehicle Buddhism was born. And Zen was established in China by indian Buhddist, Daruma because it was heretical in India. After Confucianism became major religion in China, Japan was the successor of Zen. This is the history.
This story is pertially closed to the origin of Christianity.
Zen is the practice everyone can do. Controlling anger, relieving oneself from anxiety, and exploring answers inside, not outside. That's all. The meditation is one of the methods. We can do it everywhere.
One of the key concept in Buddhism is "changing ever". Everything is unstable.
And, I realize that one of the Jobs's greatest management philosophy is to release his past. This philosophy is very closed the above concept in Buddhism. As we get old, we easily stick to our past achievement. But, it doesn't mean anything, even will be bottleneck for us to step forward simply because everything changes, which also means everything is imperfect.
I think this is why Jobs used to said "the death is the great invention" because we are forced to step forward by death.
I think it's not about religious thing, it's about philosophy every one should have.
For me, it's not important whether Jobs is a kind of Buhddhist or not. He taught us "to release past". That's a most important thing.