There are many different ways to spoke a bicycle wheel. Most bicycles have tangential spokes, meaning that the spokes do not connect from the hub to the rim in a straight line, but at an angle. There are many different patterns of tangential spokes. Occasionally bicycles will have completely radial spokes. These spokes go straight from the hub to the rim of the tire.
Wheels typically have tangential spokes.
The way in which the wheels are spoked determines how they will perform. A bicycle wheel with tangential spoking. You can spoke the front wheel completely radially, but the rear wheel had better not be spoked radially. There is no way to convey the twist of the wheel out to the rim to drive you forward. Tangential spoking helps transmit the torque from the hub out to the tires.