What is a PMBOK Guide?
The PMBOK® Guide is PMI's foundational standard for project management. The 7th edition (2021) reframed it around 12 principles (stewardship, value, tailoring, quality, leadership…) and 8 performance domains (stakeholders, team, planning, delivery, uncertainty…), replacing the process-heavy 6th-edition structure — though process-group thinking still appears on exams and in practice.
Know what it is and isn't: a guide and vocabulary, not a methodology. It describes what good project management addresses; how you do it is tailoring.
Worked example
A new coordinator asks which document tells her exactly what to do next on her project. The honest answer: none — the PMBOK Guide gives her the shared vocabulary (baselines, change control, risk register) and principles, her company's methodology gives the procedure, and her judgment tailors both to a two-month fit-out that needs a fraction of the ceremony.