Please document expected behavior when default arguments are used.
This is a documentation request.

The docs for read_csv currently include the following:

index_col: 
int, str, sequence of int / str, or False, default None
Column(s) to use as the row labels of the DataFrame, either given as string name or column index. If a sequence of int / str is given, a MultiIndex is used.

Note: index_col=False can be used to force pandas to not use the first column as the index, e.g. when you have a malformed file with delimiters at the end of each line.

#### Problem description
The docs explain how read_csv works in every case EXCEPT the default, which is the most common.  Please document what happens when index_col=None is passed.

