Zero-Based Budgeting - ZBB. A system in which a yearly budget for a department in a company starts at zero with no pre-authorised funds, and the department has to justify its budget requests.

Zero-Rated - Describes goods or services on which the buyer pays no value-added-tax.

Zero-Sum Game - A situation in which what is lost by one person, company, etc., is matched by a gain by another/others. Used in economics and Game Theory to describe the relatively simple 'strictly competitive' situation whereby all the losses and gains balance each other to zero. Potential gains are finite; what is gained by one must be lost by another, and vice-versa.

Zip - In computing, compressing data to make a file smaller in order for it to be stored or sent to another computer. Also, slang for nothing.

Z-Score - Developed by Dr Edward Altman of New York University in the 1960s, a measurement of the financial health of a company which predicts the probability of the company going bankrupt.