A CSV file, or Comma-Separated Values file, is a simple text format used to store tabular data. Each line in the file represents a row, and the values in that row are separated by commas. This format makes it easy to read and write data, as well as to import and export information between different software applications, such as spreadsheets and databases. CSV files are widely used because they are lightweight and can be opened by many programs, including Microsoft Excel and Google Sheets. They are particularly useful for data exchange, allowing users to share information without needing complex software.