Paper thickness is measured in GSM (Grams per square metre). To give you a comparison, your average copy paper is 80gsm and your average business card is 300gsm. Paper can come coated or uncoated. The coated paper typically weighs more and has a smoother surface which allows for a finer finish. Uncoated paper is typically lighter and a little more porous. It has a finish that is not as fine.

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