Unclear description of DefaultFormatter's overwrite mode

Unclear description of DefaultFormatter's overwrite mode

If we look at the Java API for DefaultFormatter, we find that you can set
it to two modes:
public void setOverwriteMode(boolean overwriteMode)
"Configures the behavior when inserting characters. If overwriteMode is
true (the default), new characters overwrite existing characters in the
model.
Parameters: overwriteMode - Indicates if overwrite or overstrike mode is
used"
The meaning of this is unclear. What is the practical difference between
overwrite and overstrike mode? Can anyone who is familiar with
JFormattedTextField or AbstractFormatters please clarify? Thanks!