The term "chemical composition" refers to the specific proportions and types of elements or compounds that make up a substance. It is an essential characteristic of any material, as it determines its physical properties, reactivity, and potential uses. The chemical composition can be determined through various analytical techniques such as mass spectrometry, X-ray diffraction, or chromatography, depending on the nature of the sample being analyzed. Understanding a substance's chemical composition is crucial for chemists in order to develop new materials and products, optimize industrial processes, and advance our knowledge of the natural world.