Introduction to Non-Destructive Testing is a clear, modern, beginner-friendly reference book for people entering the NDT field for the first time. Written in plain technical language, this book explains what NDT is, where it is used, how the main methods work, and how inspection fits into real engineering practice. It is designed for trainees, career changers, students, developing technicians, and anyone who wants a strong foundation in non-destructive testing without being overwhelmed by jargon or overcomplicated explanations. Rather than focusing on only one inspection method, this book gives readers the wider picture. It explains how NDT supports manufacturing, maintenance, quality control, safety, reliability, and asset integrity across industries such as oil and gas, power generation, aerospace, rail, transport, manufacturing, marine, offshore, and infrastructure. Inside this book, readers will find clear explanations of: What non-destructive testing is and why industry uses it Where and when NDT is used in the life of a component How product form, material type, and likely damage affect method choice The main NDT methods, including VT, PT, MT, UT, RT, ET, leak testing, and other important techniques Common discontinuity types and service damage mechanisms Method comparison tables and practical inspection scenarios Standards, codes, specifications, procedures, and acceptance criteria Certification, qualification, authorisation, and the meaning of Level 1, Level 2, and Level 3 Experience hours, supervised development, training, exams, and entering the industry Safety, reporting, traceability, and professional conduct This book has been built as both a learning guide and a long-term desk reference. It includes worked examples, revision questions, quick comparison tables, a long glossary, a topic finder, and practical planning pages to help readers revisit key subjects later. The aim is not just to give definitions, but to help readers understand how NDT thinking works in real life: what the component is, what condition matters, where that condition is likely to be, which method best answers the question, and what documents control the work. For anyone looking for a serious but accessible starting point in NDT, this book provides a strong and useful foundation. Please note: this book is an educational and reference resource. Real inspection work must always follow the approved written procedure, applicable code or standard, and the governing acceptance criteria for the job.