9. The nature of income.

Income tax is imposed exclusively on income1, but, apart from describing the various types of income brought into charge and classifying them by reference to heads of charge2, the Income Tax Acts3 attempt no comprehensive definition of income. Nevertheless, from a study of the heads of charge and as a result of judicial interpretation it is possible to establish some criteria which assist in determining the quality, with reference to taxation, of a given receipt or profit4.

To constitute income a receipt of money or money's worth is usually necessary5, although certain types of income are specifically exempt from taxation6.