What does P.A.S.M mode mean in SLR cameras?

P: program exposure mode. The camera has set exposure parameters according to photometry.

Answer: Aperture priority exposure mode means that the aperture value can be set, and the camera automatically sets the shutter speed according to the measured light.

S: shutter priority exposure mode, that is, the shutter speed can be set, and the camera automatically sets the aperture value according to the measured light.

M: Manual exposure mode is to set the aperture and shutter manually.