In the upper right corner of the screen, the console lets you enter numerical values and prompts you on parameters required by the active command.
To confirm default values, where indicated, just press the Enter key.
To skip the current and all the subsequent prompts for the current command, use the Win / Mac shortcut. Default values will be assigned to the skipped parameters.
Any parameter requiring numerical input can be either set through the keyboard or specified by working interactively in any views with the mouse. When you type XYZ coordinates, values can be separated by a comma (i.e. 1,1,1), a semi-colon, or any other key except a dot, which is used for decimals. A tab can be used as well. Spacebar, on the contrary, cannot be used as it puts an end to operations.
By default, values are inserted with respect to the object's origin but, if you type the "@" symbol near any coordinate number (i.e. @2,2,2 or 2,2@,2), they can be inserted with respect to the previously inserted point.
By typing X, Y, or Z before the coordinate, you can specify the relative position respect to the X, Y, or Z axis (i.e. x1). This way, you don't have to type all coordinate values when just one must change.