Swords may have either a straight blade or a curved one. A straight sword was primarily intended for hacking and stabbing, whilst a curved sword was better at slashing. The difference between a hacking cut and a slashing one is essentially the same as the difference between using a butcher's knife and a chef's knife; one forces an edge straight into a material while the other is pulled along the material to get more of a slicing action. Expertise with this weapon is still built around the basic straight sword techniques of poking, flicking, stabbing, dragging, short-cutting, guiding, and adhering with extremely focused power.
Historical one-handed versions have blades varying from 17.7 to 31.5 inches in length. The weight of an average sword of 28 inch blade-length would be in a range of approximately 1.5 to 2 pounds. There are also larger two-handed versions used for training by many styles of Chinese martial arts.
Twin Straight Swords (Shuang Jian) are two mirror-image weapons, one held in each hand. In modern kungfu, the practice of twin weapons balances out the left hand with the right, since many styles have a predetermined dominance.