Mail is what you receive in your mailbox, and it is correspondence of some type that can be sent physically or electronically. There are mail quotes regarding either type of mailing system. When you send physical mail then this must be processed by the post office and then delivered to the physical address listed on the envelope or package. Electronic mail, also called email, is sent over a computer network to your specified email account address. Postal mail can take several days while the electronic version arrives almost as soon as it is sent out by the sender. Mail can also refer to a specific armor or covering, like the chain mail that the knights in the past wore to protect them during contests and battles.