MCTB is the abbreviation for the title of a book called Mastering the Core Teachings of the Buddha, an Unusually Hardcore Dharma Book by Daniel Ingram.

It serves as a conceptual and terminological foundation and reference for a significant portion of the discussions on the DhO, and so reading it can be of value to understand what people are writing about and debating.

It is published by Aeon Publications and can be ordered from your local independent bookseller or the standard mega-sites such as Amazon.

A free version is also available on-line at Interactivebuddha.com.