This document discusses information formulae in Excel. It explains that information functions provide details about the data in a cell or range, such as whether it is a number, text, or empty. Some common information functions are ISBLANK(), ISERR(), ISERROR(), ISLOGICAL(), ISNA(), ISNONTEXT(), ISNUMBER(), ISREF(), and ISTEXT(). The ISBLANK() function specifically is highlighted, which returns TRUE if the referenced cell is blank. An example is provided showing ISBLANK() returning False for a non-empty cell and True for an empty cell. The document encourages the reader to learn more about these functions in upcoming presentations.