Many spells are described as magic missiles - for example, Fire Ball. In this case, the Wizard conjures a ball of flame and hurls it at a target. All magical missiles are thrown, hurled, or projected in this fashion.
A magic missile can only be cast at a target if it would be a viable target according to the rules for shooting. For example, the Wizard must be able to see the target, and individuals can only be picked out from surrounding units in the same circumstances as archers, crossbowmen or comparably armed individuals can do so. Unless otherwise noted, magic missiles hit their targets automatically.
A Wizard cannot cast these spells if he is engaged in close combat.