One is shortwave radiation or short wavelength radiation and the other is longwave radiation/long wavelength radiation. The diagram below shows the range of shortwave radiations. There is no proper definition of shortwave radiations as there is no standard cut off for near infrared radiations range.
Cottage cheese is a fresh cheese curd product with a mild flavor. It is drained, but not pressed, so some whey remains and the individual curds remain loose.
Most cheese will give you a nice amount of calcium, but cottage cheese is an exception. While it may be low in fat, cottage cheese doesn't offer much in terms of calcium, so remember to try and fit in some other high-calcium dairy products in your day such as low fat milk or yogurt. As for sodium in cottage cheese, it comes from the processing.