Patent ID: 8767396

Claim:
An information processing system including a main device, and an extension device onto which/from which the main device can be mounted/dismounted, wherein: the main device comprises: a display surface having a display screen; a back surface that is a reverse side of the display surface; a top surface, a bottom surface, and a pair of side surfaces located between the display surface and the back surface; a pair of support shafts provided on the back surface; a pair of leg portions, each having one end rotatably fixed to the pair of support shaft, respectively; and a handle member located between the other ends of the pair of leg portions, wherein: the pair of support shafts face each other with a predetermined gap therebetween in a direction parallel to the bottom surface, and the pair of leg portions, which rotate about the pair of support shafts, are each structured and arranged so that: in a first state a first surface of each leg portion contacts the back surface of the main device, and the handle member of the main device protrudes from the top surface of the main device, and in a second state a second surface of each leg portion, which is a reverse side of the first surface thereof, contacts the back surface of the main device, and the handle member is adjacent to the bottom surface of the main device; and the extension device comprises: a placement portion structured and arranged for the main device to be placed thereon; and a wall portion extending from the placement portion, the wall portion including a front end having a predetermined width smaller than the predetermined gap between the pair of support shafts of the main device, wherein: when the main device is placed on the placement portion, with the pair of leg portions in the first state, the wall portion of the extension device contacts the back surface of the main device, and the front end of the wall portion is positioned between the pair of support shafts of the main device.