Piece of data is a broad term that can refer to any type of information. In the context of a crossword puzzle, the solutions STAT (4 letters), FACT (4 letters), and STATISTIC (9 letters) all refer to different types of pieces of data. A STAT is a numerical value that is used to summarize a set of data, such as an average or a total. A FACT is a piece of information that is known to be true, such as a date or a name. A STATISTIC is a numerical value that is derived from a set of data, such as a percentage or a ratio.