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What is the difference between a background image and a logo?

Background images are applied to the full bleed size of the document you are creating (but you can reduce its size after uploading). The background image may have text and/or photo frames, and other graphics can appear on top of it.

A logo appears on top of other design elements (for example, your uploaded background image or a design that is part of a template). However, it is possible to add text on top of a logo image.