Ancient European zither psaltery
In the Christian era, a psaltery consisting of a soundboard with several pre-tuned strings that are usually plucked came into use. It was also known by the name canon from the Greek word κανών (kanṓn), which means "rule", "principle", and also "mode". The modern Greek folk instrument is called by its diminutive, kanonaki. The instrument is usually small enough to be portable; its shape and range vary.