CSV is an acronym of "Comma-separated values". It is a popular plain-text format when there is a need to import, export or simply store data in a non-proprietary format. Almost all data handling tool support CSV format, in various incarnations. You can read more about the CSV format on Wikipedia: http://en.wikipedia.org/wiki/Comma-separated_values.
The import process requires preparation, and starts with a form made of primary settings:
When changing the Entity setting, the section on the right, titled "Available fields", changes to present the expected data fields. Although the importing tool helps you by taking care of matching your file's fields with PrestaShop's, you should strive to make your data more import-friendly by following the naming scheme and order of the presented fields. If not, the import will be more tedious, but not impossible.
Some fields have a little information popup available (represented by a "i" logo), which you can display by hovering the mouse cursor over it. They mostly pertain to PrestaShop's multistore or advanced stock management features. Make sure to read them all in order to better build/edit your data files.
Imported data file must be in text-file, using a CSV-based format and the accompanying
.csv file extension. We recommend using a semicolon ";" as a field separator. If you textual data (product description and such) contains semicolons, you should either remove them, or choose another separator in the "Field separator" option.
When clicking the "Next step" button, the page reloads with the data mapping tool. This interface helps you map you file's data columns with the ones required by PrestaShop.
Presented in this table are the rows from your CSV file, placed under arbitrary columns matched to PrestaShop's database needs. It is up to you to make sure that all the columns from your CSV file are matched with the correct column header, using each header's drop-down selector, so as to import your content correctly.