iTunes Digital Gift Cards are a convenient and secure way to purchase music, movies, TV shows, apps, books, and more from the iTunes Store, App Store, Apple Books, and Apple TV. 
 
Benefits of using iTunes Digital Gift Cards:
Convenient: Gift cards can be purchased online and redeemed instantly in the iTunes Store, App Store, Apple Books, and Apple TV.
Secure: Gift cards are a safe and secure way to purchase content from Apple, as they do not require you to share your credit card information with Apple.
Flexible: Gift cards are available in a variety of denominations, so you can purchase exactly the amount of content that you need.
Giftable: Gift cards can be purchased as a gift for friends or family members who love to use Apple products.
 
How to redeem an iTunes Digital Gift Card:
Open the App Store app on your iPhone, iPad, or iPod touch.
Tap on the "Today" tab.
Scroll down and tap on "Redeem Gift Card or Code".
Enter the gift card code and tap on "Redeem".
Your gift card balance will be added to your account immediately. You can then use your gift card balance to purchase content from the iTunes Store, App Store, Apple Books, and Apple TV. 
 
Additional things to keep in mind about iTunes Digital Gift Cards:
Gift cards are valid for 12 months after purchase.
Gift cards cannot be transferred to other accounts.