The CSV format
The comma-separated values (or CSV) file format is a delimited data format that has fields separated by the comma character and records separated by newlines. (See the Wikipedia).
It is written in plain text, thus it is also human readable. This could be an example:
"Column A", "Column B", "Column C", "Last column" 16.66, -1.83160170199, -16.66, -1.76137459682 16.33, -1.46988075813, -16.33, -1.78263420735 16.0, -1.4500352931, -16.0, -1.50469469065 15.66, -1.48060090576, -15.66, -1.59230864037
Importing CSV files in OpenOffice Calc
Select Sheet From File... from the Insert menu and choose the file you wish to import. In the Separator Options panel, choose Comma and hit OK twice.
Importing CSV files in Microsoft Excel
Files that have the .csv extension are recognized by Excel. If the file has a .txt or unknown extension, the Text Import Wizard will be run. In order to import the file as CSV, select the Comma as the delimiter character.