This tool rotates selected vertices around the position of the 3D Cursor in the active window.
Click (press and release the left mouse button) without moving the mouse to place the 3D cursor at the coordinates you want to be the center of rotation. Click in a window and drag the mouse to the left or right to interactively rotate the selected vertices around the 3D cursor.
Rotation occurs around an axis passing through the 3D Cursor and running in and out of the screen. The axis is through the active window. Rotation starts when the mouse is moved after pressing the left mouse button.
To rotate by a specified angle, double-click on the Rotate Tool to bring up the Rotate dialog.
To rotate interactively by 1░ increments, use the left or right arrow keys. To rotate interactively by 5░ increments, hold down the SHIFT key while using the left or right arrow keys.