I mean light emit some rays doesn't it? light emit some rays to objects objects reflect them and therefore we see the objects
Is it not the way we see objects?
I asked this question because we don't see x-rays and x-rays are such rays that we can see the inside of the objects.
but with normal light why can't we see the inside of objects? If we saw the x-rays we could see whatever the x-ray machines see right?
Our eyes can see electromagnetic rays in only a very narrow part of the spectrum (light rays). These reflect off some objects and penetrate others (glass, clear plastic, etc.). Other parts of the e-m spectrum have different interactions with matter. Try Wikipedia - it would take a whole book to get into all the details you might be interested in.
A lightbulb emits electromagnetics waves. A ray is simple way to imagine electromagnetic (EM) waves.
EM waves come in many wavelengths. If the wavelength is 400 nm and 700 nm, it affects our eyes (retina) and we call this vision. If the wavelength is above this, it affects our skin (thermoreceptors http://en.wikipedia.org/wiki/Thermoreceptors).
If the wavelength is below 400 nm (UV, x-rays, gamma rays), it can break up (bio-)molecules permanently, disrupt their function, and eventually cause cancer.