X-ray examination is a fast and painless procedure that allows display of structures, especially bones in your body.
X-rays can pass through your body. However, they are absorbed depending on the density of the material they have passed through. Dense materials such as bones and metal appear white in x-ray films. Air in lungs appear black. Fat and muscle appear in shades of gray .
In some types of x-ray test, contrast agents such as iodine or barium are given to obtain more detail in x-ray films.