Here you can enter an angle by which the current frame is to be rotated. You can rotate text frames in 1/100 degree increments and raster graphic frames in 90 degree increments. The point of rotation is always the centre-point of the frame. To set the angle, which is measured counter-clockwise, click on the numeric field, enter the angle, and press [Return].
The frame will not be rotated immediately. When you select a frame, its angle of rotation will appear in this field, which you can of course also alter if you wish in the way described.