Complex sentence: A superscript is a number, figure or indicator, that appears above the normal line of type, when used in a formula, mathematical expression or description of a chemical compound, and to indicate the presence of a footnote in a document.
Split into simpler sentences: A superscript is a number, figure or indicator, that appears above the normal line of type. Superscripts can also be used to indicate the presence of a footnote in a document.