I have a knob on the right side of my tummy what can it be?

Question is unclear: In that area are the liver, gallbladder, part of the intestine, and of course some muscle and ribs. The right kidney is deeper inside, near there. One's primary care doctor can examine to see if there is any reason to worry. A patient can write down details such as when the knob started, inside or outside the tummy, was there any trauma (like in sports), etc., and show the details to one's doctor.