The basic difference between the two shapes :
A cross ,two lines crossing and dividing one ore two lines in half . an ancient human symbol and is used in many religions
A star , a shape with more than 4 points . on a clear night you can see many stars in the sky
The shapes do not have to be symmetrical with right angels
Stars are shaped as a closed line and can have many intersecting lines .
Crosses are shaped with 2 lines the lines intersect at a point.