When you carry something, you hold it and take it somewhere. When you live in a walk-up apartment, you have to carry bags of groceries up several flights of stairs.
You carry armfuls of books home from the library, or carry your new puppy when she gets tired on a long walk. You might also carry friends in your car, or carry plenty of cash in your wallet. In any of these cases, you're transporting something. If you're ill and can spread germs to other people, a doctor might say that you carry an infectious disease. The words carry and car share a common Latin root, carrum, "two-wheeled chariot."