The gravitational field which is created during a star collapse to a single small point known as a Singularity with infinite density, will be so strong that nothing can scape, not even light! That is a simple concept of Black Hole. Some effects of black hole include twisting and distorting light as it passes the black hole or about the body, Spaghettification phenomenon would occur; That means Body stretching begins as becoming closer to singularity point.