Encryption is the act of encoding data using algorithms to hide the real values in a way that allows you to decode the data at a later time when it is needed.

Oracle/MSSQL/MySQL Transparent Data Encryption (TDE):

TDE is product-specific and provides the ability to encrypt data in the database without the need for changes to the code or applications that access the data.

Vormetric Data Security Platform:

Simple one-stop, data-at-rest security. Vormetric offers TDE as well as other key management solutions. The platform offers a single management console to manage all encoding, key management, and related security intelligence enterprise-wide.