A washing machine includes a water tub arranged in a case and a damper installed between the case and the water tub for damping vibrations of the water tub. The damper includes a plunger having one end supported on the case; a rod having one end supported on the water tub and the other end movably inserted to the plunger; a housing arranged to wrap around some of the plunger and the rod and including a friction member arranged between the housing and the plunger to contact an outer circumferential surface of the plunger; and a switching device configured to be in a first state in which the rod is coupled to the housing and able to move within the plunger along with the housing and a second state in which the rod is decoupled from the housing and able to move solely within the plunger.