An interface operation method used for a computer system, wherein the computer system comprises an input device and a display device, the computer system provides a plurality of functional interfaces (510, 520), the display device is used for displaying a current functional interface of the functional interfaces (510, 520), the functional interfaces (510, 520) comprise an arrangement order (D1, D2, D3, D4) and each functional interface (510, 520) comprises a plurality of message areas (512a, 512b, 512c, 514a, 514b, 522a, 522b, 524a), and the interface operation method comprises: receiving (S210, 410, 610) an input through the input device; determining (S220, S420) whether the input conforms to a first operation; and switching (S230, S430, S630) the current functional interface to another functional interface of the functional interfaces (310, 320, 330, 340, 350) according to the arrangement order (D1, D2, D3, D4) when the input conforms to the first operation, determining (S220, S420) whether the input conforms to a second operation if the input does not conform to the first operation; and selecting (S240, S640) one of the message areas (512a, 512b, 512c, 514a, 514b, 522a, 522b, 524a) of the current functional interface when the input conforms to the second operation, wherein the message areas (512a-512c, 514a-514b, 522a-522b, 524a) of the current functional interface (510, 520) are divided into a first message area group (512, 522) and a second message area group (514, 524), and the step of selecting one of the message areas of the current functional interface when the input conforms to the second operation comprises: selecting one of the message areas (512a-512c, 522a-522b) from the first message area group (512, 522) when the input conforms to a third operation; and selecting one of the message areas (514a-514b, 524a) from the second message area group (514, 524) when the input conforms to a fourth operation, and characterized in that the input device is a keyboard, wherein each of the first operation, the second operation, the third operation and the fourth operation is a press of a different specific key or key combination of the keyboard. receiving (S210, 410, 610) an input through the input device; determining (S220, S420) whether the input conforms to a first operation; and switching (S230, S430, S630) the current functional interface to another functional interface of the functional interfaces (310, 320, 330, 340, 350) according to the arrangement order (D1, D2, D3, D4) when the input conforms to the first operation, determining (S220, S420) whether the input conforms to a second operation if the input does not conform to the first operation; and selecting (S240, S640) one of the message areas (512a, 512b, 512c, 514a, 514b, 522a, 522b, 524a) of the current functional interface when the input conforms to the second operation, wherein the message areas (512a-512c, 514a-514b, 522a-522b, 524a) of the current functional interface (510, 520) are divided into a first message area group (512, 522) and a second message area group (514, 524), and the step of selecting one of the message areas of the current functional interface when the input conforms to the second operation comprises: selecting one of the message areas (512a-512c, 522a-522b) from the first message area group (512, 522) when the input conforms to a third operation; and selecting one of the message areas (514a-514b, 524a) from the second message area group (514, 524) when the input conforms to a fourth operation, and characterized in that the input device is a keyboard, wherein each of the first operation, the second operation, the third operation and the fourth operation is a press of a different specific key or key combination of the keyboard. selecting one of the message areas (512a-512c, 522a-522b) from the first message area group (512, 522) when the input conforms to a third operation; and selecting one of the message areas (514a-514b, 524a) from the second message area group (514, 524) when the input conforms to a fourth operation, and characterized in that the input device is a keyboard, wherein each of the first operation, the second operation, the third operation and the fourth operation is a press of a different specific key or key combination of the keyboard.