Double-entry accounting (See Chapter 4 of the Vernimmen)

A company’s assets and liabilities must be exactly equal. This is the fundamental principle of double-entry accounting. When an item is purchased, it is either capitalised or expensed. If it is capitalised, it will appear on the asset side of the balance sheet, and if expensed, it will lead to a reduction in earnings and thus shareholders’ equity. The double-entry for this purchase is either a reduction in cash (i.e. a decrease in an asset) or a commitment (i.e. a liability) to the vendor (i.e. an increase in a liability)