This document provides an introduction to the General Data Protection Regulation (GDPR). It begins by defining GDPR and explaining why it is important. It describes the evolution of GDPR from earlier data protection directives and regulations. It then defines several key terms related to GDPR, such as personal data, sensitive data, processing, pseudonymisation, and anonymisation. It outlines the structure of GDPR including its 11 chapters and 99 articles. It also describes various roles defined in GDPR such as controller, processor, data protection officer, and supervisory authority. Finally, it summarizes the six key GDPR principles and six lawful bases for processing personal data.