To have your CD professionally manufactured at a pressing plant, a DDP image is required.

What is a DDP Image :

A DDP image is the professional industry standard format used for CD manufacturing. It contains all audio data, track order, spacing, and CD text in one secure package.
A DDP image is required if you want to have your music pressed on CD and is sent directly to the pressing plant to ensure your CDs are produced exactly as intended, without quality loss or errors.