A more thorough explanation:

Definition: Franking privilege is the ability of certain government officials, like members of Congress and federal courts, to send mail for free without using postage stamps. They can use their signature, stamp, or mark instead of paying for postage.

Example: A member of Congress wants to send a letter to a constituent. Instead of buying a stamp, they can use their signature or stamp to indicate that the mail is being sent under the franking privilege. This means that the mail will be delivered without the need for postage.

This example illustrates how the franking privilege works. It allows government officials to send mail without having to pay for postage, which can save them a lot of money. However, this privilege is only available to certain officials and is subject to certain restrictions.