Did you know that all paper and board contains water? Under normal conditions, about six per cent of its weight is water. This is known as its moisture content. At the beginning of the papermaking process, paper contains 99% water, but this amount is gradually reduced by a combination of gravity, compression and heat as it goes through the paper machine. Many years ago (before quality specifications) mills tried to produce paper with the highest water content possible as this meant the customer would be paying a high price for paper which had little fibre content, therefore it was fairly expensive to produce. Those days are long gone as papermakers have realised the importance of getting the moisture content right. If the amount of water is not just right, the paper will have undesirable qualities such as curling up during printing or conversion, or being the wrong strength or stiffness. For instance, photocopy paper needs a very low water content to ensure good feeding and clean copies. That is why it is important to only unwrap what paper you need for the job in hand. Moisture from the air will penetrate opened reams and the quality of the paper can deteriorate rapidly.