45 Comma Separated Values Dataset A comma-separated values (CSV) file stores tabular data (numbers and text) in plain text. Plain text means that the file is interpreted a sequence of characters, so that it is human-readable with a standard text editor. Each line of the file is a data record. Text 1 Digital Preservation Department / The National Archives 02 Aug 2005 03 Aug 2015 text/csv MIME x-fmt/18 PUID csv File extension