Consumer theory is the study of how individuals make decisions about what goods and services to consume, given their budget and preferences. In the field of economics, this theory is commonly referred to as "microeconomic theory" or "consumer choice theory". Other synonyms for consumer theory include "economic theory of consumption" and "utility theory". The concept of consumer theory has applications not only in economics but also in marketing and psychology, where it can help explain consumer behavior and choices. Understanding the basic principles of consumer theory is essential for businesses and policymakers to make informed decisions about marketing strategies, pricing, and public policy.