For more than a century, the basic specifications of playing cards have changed little. The standard size of playing cards is 2.25×3.5 inches, while the size of playing cards in bridge is slightly narrower, with a size of 2? ×3? Inches, so that the player can hold 13 cards in one hand. The paper card for printing playing cards consists of two pieces of thin paper, which are bonded together with black adhesive. It is impossible to print on both sides with a single layer of thick paper; Because if there is light behind a player, the player opposite the player can see the cards in the previous hand through the light. Black adhesive will make playing cards opaque. ) So playing cards are sometimes called "sticky cards".

Modern players are used to using "double-headed cards", which is convenient no matter which side they look at; At the same time, this kind of card is marked with corner codes at two opposite corners, so you can know what card it is without looking at the whole card face. It was not until the late 1970s that 19 became the standard form. Before that, players had to see the whole card face to know what it was, and they had to hold it straight in their hands to see it clearly.

Perhaps because of superstition or habitual influence, the pattern design of playing cards has not changed significantly. There have been many attempts to print four designs in four colors, change the shape of design symbols, change the headboard into modern clothes and use round cards, but these attempts have not been successful. For example, the Soviet Union tried to replace the traditional images of kings and queens in playing cards with the images of revolutionary heroes, but in the end, traditional playing cards were still popular.

1964 has made a more modern change, and it has been adopted in the competition card of the world Olympic team competition. This is that the card surface uses a very light blue-gray color instead of white as the background color. Facts have proved that this change can reduce the tension in the eyes. The world bridge championships 1967, 1968 and 1969 all adopted the playing cards with this light blue-gray background color.

Because of the limited durability of paper, inventors have been developing more durable substitutes than paper for many years. 1932, Sigfried Krassler registered a patent right in Austria and other European countries, which was used to manufacture non-flammable opaque plastic sheets, and used this sheet to print playing cards with ink made from its matrix plastic. He produces plastic poker with the trademark "Milla Kerr" (meaning miracle). Later, he sold the European part of the patent, but kept the patent in the United States.