The study of individual markets of demand and supply, where the decision makers are individual consumers, workers, or firms that try to maximise their satisfaction or profits, is known by which branch of economics?

Introduction / Context:
Economics is broadly divided into two main branches: microeconomics and macroeconomics. Each branch looks at different levels of analysis and uses different tools to answer economic questions. This question asks you to identify which branch focuses on individual markets and decision makers such as households and firms that aim to maximise satisfaction or profits. Knowing this distinction is fundamental for organising further economic knowledge.

Given Data / Assumptions:

• The description emphasises individual markets, not the economy as a whole.
• The decision makers are described as individual consumers, workers, and firms.
• These decision makers are presented as trying to maximise personal welfare or profits.
• The options include macroeconomics, econometrics, microeconomics, and heterodox economics.

Concept / Approach:
Microeconomics is the branch of economics that studies the behaviour of individual economic units such as consumers, workers, firms, and specific industries. It examines how they make decisions about what to buy, what to produce, and how much to work, under the constraint of limited resources. It also studies how these decisions interact in specific markets of demand and supply, leading to prices and quantities. Macroeconomics, in contrast, studies aggregates such as national income, unemployment, inflation, and overall growth. Econometrics provides statistical tools for economic analysis, and heterodox economics is a broad term for approaches that depart from mainstream theory.

Step-by-Step Solution:
Step 1: Identify the level of analysis described in the question. It clearly refers to individual markets and individual decision makers.Step 2: Recall that microeconomics deals with such individual units and market level phenomena.Step 3: Macroeconomics instead looks at aggregate variables for entire economies, which is not what the question describes.Step 4: Econometrics involves the use of mathematical and statistical techniques to test economic theories, but it is a method, not a branch focused solely on market structure.Step 5: Heterodox economics is a collection of alternative schools of thought, not a standard label for the basic study of demand and supply in individual markets.Step 6: Therefore the correct term for the study described is microeconomics.

Verification / Alternative check:
Introductory economics courses and textbooks are often titled Principles of Microeconomics when they discuss demand and supply, consumer choice, production costs, market structures like perfect competition and monopoly, and firm behaviour. On the other hand, books titled Principles of Macroeconomics discuss inflation, unemployment, budget deficits, and monetary policy. By checking how these topics are grouped, you can verify that analysis of individual markets and decision makers belongs under microeconomics.

Why Other Options Are Wrong:
Macroeconomics: Focuses on overall economic aggregates and policies rather than specific markets and individuals.

Econometrics: Provides quantitative methods used in both micro and macro studies and is not itself the branch defined in the question.

Heterodox Economics: Refers to non mainstream schools of thought and does not denote the standard study of individual markets.

Common Pitfalls:
Learners sometimes confuse the terms micro and macro because both words refer to economic analysis and both are often discussed in the same course. A simple way to remember the difference is to associate microeconomics with microscopes and small units, while macroeconomics is like a wide angle lens looking at the whole economy. When a question stresses individual behaviour and specific markets, it usually points to microeconomics.

Final Answer:
The study of individual markets and decision makers is called microeconomics.