What instruments are pianos, accordions, etc?

Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range.

Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range. Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range. Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range. Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range. Piano and accordion are both keyboard instruments, and keyboard instruments are the general name of instruments whose keys are arranged like piano keyboards. Each key on these instruments has a fixed pitch, so it can be used to play any music in its range.