IDF assumes that the separator for data-fields is a comma; enclosing the data-values in each field in a pair of single-quotes or a pair of double-quotes as well is optional.
SEPARATOR = "s"
placed in a FILE tag defines s as the separator instead. In this example s is set to ; so that
<FILE FILENAME = "ADDRESS2.CSV" SEPARATOR = ";" />
can be used for a data file with fields separated by semicolons.
Note: if you set the separator to be a comma explicitly, i.e.
you can force any quotes to be treated as part of the field data.