what is encrypted email?

Answer 1

For a full explanation:

http://www.ephesus.com/Encryption/Encryption.html

Answer 2

It is email that has been encrypted, encoded so that you can't read it unless you have the code to decrypt it. Popular options to encrypt email are PGP or GPG, which are somewhat compatible.

Basically, you give out a public key that will let people encrypt email they are going to send to you, when you get it, you can decrypt it using a private key that is the only key that can decrypt the message.