What is encryption?
Encryption is a way to enhance the security of a message or file by scrambling the contents so that it can be read only by someone who has the right encryption key to unscramble it. For example, if you purchase something from a website, the information for the transaction (such as your address, phone number, and credit card number) is usually encrypted to help keep it safe. Use encryption when you want a strong level of protection for your information.
For more information, see What is Encrypting File System (EFS)?