Newbie - Black holes(spots) while modeling

[Anonymous]

Not really expierenced with the program and I've encountered this so called "problem". Basically when I start modeling basic shapes and then render them i get this black opening that isn't there in the first place. I can't seem to figure why is this thing shown on my render window. When I  try to look around the shape I just cannot find it. Why is this occuring? (1- surface above) (2 - bottom) (3- rendered)

[bob.bernstein]

If you just render an object ONLY, there is nothing for light to reflect on behind the object, so there is no light reaching the camera.  Thus...blackness.  If you want to see something  behind your object, you have to put something there.  You could build a box or just make a sphere with your object, lights and camera inside, make sure the normals of the sphere or box face the camera.  If you want to manipulate the object for animation, you can set backface cull on the sphere or box, so only the camera sees it, but you look right through it from outside.