In plain words
A pre-authorized debit (PAD) is permission you give a company to take money from your bank account on agreed dates. It is the usual term in Canada; in the U.S. the same idea usually runs over ACH.
Why it matters
Loan apps often ask for a PAD so repayments happen automatically. Read the agreement for the dates and amounts, and for how to change or cancel it. Several provinces limit how many times a payday lender can retry a failed debit.
Example
Illustrative example: You agree to two payments of $160 on the 1st and 15th. The lender withdraws $160 on each date. If you need to change a date, contact the lender before the debit and ask your bank how to stop or dispute a debit you did not authorize.
Always read the term in the context of your own agreement and local law.