'Dose' is a general term applied to the quantity of Ionising Radiation received by an exposed body (person, part of a person or object). Some degree of care is required when using the word 'dose' since it can mean a number of different quantities. Furthermore it is more often useful to express the dose in units which give the magnitude of damage sustained or perhaps the risk of cancer induction at some time after exposure. It is usually more useful to prefix (or postfix) terms which identify the quantity under consideration, e.g. Absorbed Dose, Effective dose, Dose Equivalent. At a fundamental level, 'Dose' may be best described as 'the amount of radiation absorbed per unit mass of material with which it interacts with'.