This chapter introduces large language models (LLMs) and their transformative potential within the finance industry. It explores how advancements in natural language processing have led to the development of sophisticated models capable of automating complex financial analyses, enhancing risk management, and driving strategic decision-making. By understanding what LLMs are and how they apply to finance, you will gain insight into the opportunities and considerations of using these models in a sector that demands precision, reliability, and ethical responsibility.