In accordance with the ISO 216 paper sizing system, the weight of paper is expressed in grams per square metre (gsm). Printing paper is generally between 60gsm and 120gsm. 80gsm is standard. Anything heavier than 160gsm is considered card. A higher gsm tends to imply a thicker, and therefore stiffer, card.
Using coloured card
Colours affect our mood and create emotional associations. Coloured office supplies can thus be used to portray ideas and themes associated with certain colours. Pink, for example, can communicate femininity and tenderness while green is commonly associated with the environment. Why not use cards in presentations and workshops to convey different moods and ideas?