Generative AI has significantly advanced, particularly in natural language processing, exemplified by models like ChatGPT, but these advancements have raised concerns about misuse, such as generating fake news or plagiarizing content. This tutorial explores text watermarking as a solution, embedding detectable patterns within AI-generated text to verify its origin. We will cover the evolution of text watermarking, its modern techniques, and challenges, along with model watermarking for copyright protection. Participants will gain a solid understanding of watermarking methods, their practical applications, and future research directions in this critical field.