Book excerpt: This book is Part 1 of Cat I Prep I Package (8 parts) which is designed to help you prepare and pass Vibration Analyst Category I certification exam. Each part covers certain topics of the Body of Knowledge according to ISO 18436-2 standard. The questions are arranged in the Package to provide the best learning experience. Part 1 contains 111 questions on 'Principles of Vibration'. Cat I Prep I is the first package of its kind as it addresses all topics in the ISO standard for Category I in a form of question banks. All exam candidates can rely on the question banks, as the package is not biased towards a specific certifying body. The package offers more than 777 questions that are 12 times the questions in a real exam. Cat I Prep I meets and exceeds the standard requirements. The overall difficulty of Cat I Prep I is a bit higher than Cat I real exams in order to strengthen your readiness before taking the real exam.