What is the difference between 'Apply' check box" and 'Prepayment On Invoice' check box?

http://aporaclepayables.blogspot.com/2017/06/what-is-difference-between-apply-check.html

Let us discuss the issue with the help of an example.

Prepayment Invoice -> amount=1000
Standard Invoice -> amount=10000

Apply check box: this is checked when the Prepayment amount has been paid and Supplier sends a Standard Invoice for 10000 (not deducting the Prepayment amount). Then when trying to apply the Prepayment invoice, check the 'Apply' check box.
Using the example:
Invoice Header will be 10000
Invoice Line line will be 10000
Invoice Distributions will be 10000
On applying prepayment: the prepay line for 1000 is created.

Prepayment On Invoice check box: checked when the Prepayment has been paid and Supplier sends a Standard Invoice for 9000 (deducting the Prepayment amount ). Then when trying to apply the Prepayment to Standard Invoice, check the 'Prepayment On Invoice' check box.
Using the example:
Invoice Header is 9000
Invoice Line is for 10000
Invoice Distributions are for 10000