Substrate is a term used in printing (mainly industrial printing) to describe the base material onto which images will be printed. Base materials include (though are not limited to):

• films,
• foils,
• textiles,
• fabrics,
• plastics,
• any variety of paper (lightweight, heavyweight, coated, uncoated, paperboard, cardboard, etc.), or
• parchment.

The end use of the printed product is the main factor used in determining the substrate. For example:

• A daily newspaper has a very limited life span of one day and is sold at a nominal cost. Because durability and longevity are not needed, a paper that has a low cost and low quality is chosen to be the substrate - newsprint.
• In contrast, a monthly magazine requires bold and sharp graphics and images (for the pictures and illustrations in articles, and for the advertisements). It also requires durability and longevity (because the magazine will read multiple times, over a period of time). Therefore, a high quality more expensive gloss paper is chosen.