Voucher codes are used for discount purpose when booked through the booking engine. You can for example use specific words or phrases.
To create voucher codes you go to:
Settings -> booking engine -> voucher codes
There you see three options - Phrase, Discount and Type.
Phrase: In this line you can input the word or the phrase you want the customer to use to get the discount on the booking.
Discount: Here you input the discount number or the fixed amount.
Type: You can choose between fixed amount og percentage.