The branch of science that focuses on the study of matter and its interactions is chemistry. This field explores the composition, structure, properties, and changes of matter, as well as the various chemical reactions that occur between substances. Chemistry is categorized into several subfields, including organic, inorganic, analytical, and physical chemistry. It plays a crucial role in understanding the material world, influencing areas such as biology, physics, environmental science, and medicine, thus impacting daily life significantly.