A mailbox is a container used for receiving and sending letters and packages. It is usually found outside homes or businesses, allowing postal workers to deliver mail easily. People can also drop off outgoing mail in the mailbox, making it a convenient way to send letters to friends and family. In many neighborhoods, you will see different styles of mailboxes, from simple metal boxes to decorative wooden ones. Some mailboxes even have flags that indicate when there is outgoing mail. The United States Postal Service and other postal services around the world rely on mailboxes to help keep communication flowing.