There are three different types of Buddhism – Mahayana, Theravada, Zen.
Theravada is considered the original teachings of the original Buddha. Buddha gave long speeches to a group of people called the Arhats. The Arhats are the original disciples of Buddha, they had all reached a level of understanding and wisdom and were thus put into positions of recording the Buddhas’ lectures, lessons and teachings. These volumes were placed into books and titled according to the teachings. Theravada Buddhists commonly live in Southeast Asia, Cambodia, Vietnam, Laos etc. They believe that people reach enlightenment over many lifetimes, although it can be attained instantly in are spiritual cases.
Mahayana Buddhists live in Tibet, China, Korea and Japan, they do not follow the original teachings, they believe that the Buddha went to other areas of the mind and thought (best description I can give) to communicate with past spirits called Devas. Devas keep the sacred teachings which are only shared with enlightened beings. These are the sacred teachings of Mahayana buddhism.
Zen is a limb of Mahayana Buddhism, Zen is a mixture of Buddhism and Taoism that developed in eastern China. Although zen embraces many aspects of presence, mindfullness. Though sharing some of the same values many consider it miles away from the original message of the Buddha.
I personally was taught Theravada buddhism and embraced most of its teachings, but I certainly value and appreciate the grounded, realist aspects of questioning and living under a more zen teaching and atmosphere. Whats important here is that regardless of our teachings and choices we honor the common grounds of understanding, learnings, growth and respect. For what is hared there leads us all to more love and more gratitude.
Peace and Love, Jim