An electronic device (102, 200) comprising: an input data receiver configured to receive input data from a user through the electronic device (102, 200), wherein the input data are various manipulations performed by the user on a screen of the electronic device (102, 200) as a control operation in order to control the electronic device (102, 200); a unit expression recognizer configured to recognize a unit expression from the performed control operation of the input data, wherein a unit expression refers to a closed curve (401, 501), a line (402, 502) or a point input by the user; and a screen controller configured to determine the control operation for controlling the screen of the electronic device (102, 200) in consideration of the recognized unit expression and control the screen in response to the control operation that is a combination of at least two unit expressions; wherein the screen controller is further configured: to enlarge, based on a zoom scaling factor, a particular area related to a closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an outward line from a boundary of the closed curve away from the closed curve on the screen, wherein the screen controller is further configured to determine the zoom scaling factor of the particular area based on a distance from a center of the closed curve to the closed curve and a length of the outward line; and/or to reduce, based on a reduction ratio, the particular area related to the closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an inward line from the boundary of the closed curve into the closed curve on the screen, wherein the screen controller is further configured to determine the reduction ratio of the particular area based on the distance from the center of the closed curve to the closed curve and a length of the inward line. an input data receiver configured to receive input data from a user through the electronic device (102, 200), wherein the input data are various manipulations performed by the user on a screen of the electronic device (102, 200) as a control operation in order to control the electronic device (102, 200); a unit expression recognizer configured to recognize a unit expression from the performed control operation of the input data, wherein a unit expression refers to a closed curve (401, 501), a line (402, 502) or a point input by the user; and a screen controller configured to determine the control operation for controlling the screen of the electronic device (102, 200) in consideration of the recognized unit expression and control the screen in response to the control operation that is a combination of at least two unit expressions; wherein the screen controller is further configured: to enlarge, based on a zoom scaling factor, a particular area related to a closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an outward line from a boundary of the closed curve away from the closed curve on the screen, wherein the screen controller is further configured to determine the zoom scaling factor of the particular area based on a distance from a center of the closed curve to the closed curve and a length of the outward line; and/or to reduce, based on a reduction ratio, the particular area related to the closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an inward line from the boundary of the closed curve into the closed curve on the screen, wherein the screen controller is further configured to determine the reduction ratio of the particular area based on the distance from the center of the closed curve to the closed curve and a length of the inward line. to enlarge, based on a zoom scaling factor, a particular area related to a closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an outward line from a boundary of the closed curve away from the closed curve on the screen, wherein the screen controller is further configured to determine the zoom scaling factor of the particular area based on a distance from a center of the closed curve to the closed curve and a length of the outward line; and/or to reduce, based on a reduction ratio, the particular area related to the closed curve in response to the control operation comprising the user drawing the closed curve on the screen and then drawing an inward line from the boundary of the closed curve into the closed curve on the screen, wherein the screen controller is further configured to determine the reduction ratio of the particular area based on the distance from the center of the closed curve to the closed curve and a length of the inward line.