A cube is a 3D solid shape. A Cube has 6 square-shaped flat faces, 8 vertices and 12 edges. While defining the sides o f a 3D figure, you do not define the number of sides but the number of edges.
1 Additional Answer
If you want to know how many sides does a cube have you can get a dice and count them. A cube has 6 sides or 6 faces (front and back, left and right, and top and bottom).