Clicking on a 'Buy now' button immediately takes you to the PayPal checkout where you buy that single digital download or a single physical item.
Buy now buttons are used where you only have a few items to sell and you do not expect purchasers to buy more than one item at a time.
The button or buttons may be placed anywhere on an existing web page which makes it easy to integrate into an existing design. The web page can be of php extension or an ordinary htm page.
<input type="hidden" name="recid" value="6">
<input type="image" src="https://
When the purchaser clicks on the buy now button, the php script will extract all the relevant data from the database and post it to the PayPal server.