贝斯手是演奏贝斯（贝司）的音乐家，而贝司一词至少可以指两种乐器：低音提琴和电贝斯（又叫低音吉他），所以笼统地来讲，贝司手亦可分别指称低音提琴家或电贝司手。但在一般口语中，贝司手更多地指的是摇滚乐中演奏电贝司的人，如照片所示。

1960年代初期，电贝斯成为摇滚乐、爵士乐、重金属音乐、乡村音乐、雷鬼乐和流行音乐重要乐器。

而低音提琴是古典音乐和爵士乐中的常用乐器。低音提琴和电贝司唯一的共同点在于两者的定弦和音域近似，除此以外，无论是乐器形制、演奏方法，均无共同之处。近年来，低音提琴越来越多地出现在摇滚乐队中。

A bass player, or bassist, is a musician who plays a bass instrument such as a double bass, bass guitar, keyboard bass or a low brass instrument such as a tuba or sousaphone. Different musical genres tend to be associated with one or more of these instruments. Since the 1960s, the electric bass has been the standard bass instrument for rock and roll, jazz fusion, heavy metal, country, reggae and pop music. The double bass is the standard bass instrument for classical music, bluegrass, rockabilly, and most genres of jazz. Low brass instruments such as the tuba or sousaphone are the standard bass instrument in Dixieland and New Orleans-style jazz bands.