CSV stands for Comma Separated Value.
CSV files are simple text files created by databases to export data. Each record is on one line, separated by a return. Within each record, the data fields are separated by a comma, even if the field is empty, so the number of commas in each line is consistent. Virtually any program can take the information from a .csv file and turn it into a table or a set of tabbed columns. More sophisticated programs can turn .csv files into complete documents, even catalogs with images and complex formatting. CSV files are the workhorses of data-based publication. They make it possible to build documents quickly and easily, starting with something as simple as an entry screen or a spreadsheet.