It's possible to assign units (single units or groups of units) or buildings to the number keys of the computer keyboard (assign: select unit, unit group or building, then press and hold Ctrl and simultaneously press the desired number, select: press number, pressing twice will jump to the unit's/building's position on the map).
Press and hold the Ctrl key and click on the location you wish to attack (It's called force fire command and is a standard feature in many RTS games, you can even fire on your own units and buildings this way.).
