The book "Formal Concept Analysis" offers a comprehensive introduction to the discipline of formal concept analysis (FCA), which deals with the formalization of concepts and conceptual thinking. FCA is based on the solid foundations of lattice and order theory and is regarded as a mathematical discipline. However, the motivation and guiding principles of FCA are strongly influenced by philosophy. In practice, FCA provides a powerful framework for the qualitative and formal analysis of data, demonstrated in numerous applications across various fields. A central feature of FCA is the emphasis on a human-centered information processing approach, supported by visualization techniques capable of revealing the inherent structure of data in an intuitive manner. This helps to structure and navigate the ever-growing amount of information in our evolving information society and supports the process of transforming data into information and ultimately into knowledge.