A wearable device worn on a body of a user is provided. The wearable device includes a sensing unit configured to sense state information of the user, a touch input unit configured to receive a touch input from the user, a controller configured to select at least one of a plurality of strings based on the state information when the touch input is received, a display configured to display the selected at least one string, and a communicator configured to transmit a message including the at least one string to a receiver device.