Articles in economics journals are usually classified according to the JEL classification codes, a system originated by the Journal of Economic Literature

Journal of Economic Literature

The Journal of Economic Literature is a peer-reviewed academic journal on economy published by the American Economic Association. It was established in 1963 as the Journal of Economic Abstracts. As a review journal, it mainly features essays and reviews of recent economic theories...

. The JEL is published quarterly by the American Economic Association

American Economic Association

The American Economic Association, or AEA, is a learned society in the field of economics, headquartered in Nashville, Tennessee. It publishes one of the most prestigious academic journals in economics: the American Economic Review...

 (AEA) and contains survey articles and information on recently published books and dissertations. The AEA maintains EconLit

EconLit

EconLit is an academic literature abstracting database service published by the American Economic Association. The service focuses on literature in the field of economics. EconLit covers articles and other materials dating back to 1969. It uses the JEL classification codes for classifying papers...

, a searchable data base of citations for articles, books, reviews, dissertations, and working papers classified by JEL codes for the years from 1969. A recent addition is indexing of economics-journal articles from 1886 to 1968.

Many articles in economics journals also list relevant JEL codes (for example JEL: B12), facilitating their use across search engine

Search engine

A search engine is an information retrieval system designed to help find information stored on a computer system. The search results are usually presented in a list and are commonly called hits. Search engines help to minimize the time required to find information and the amount of information...

s. Other extensive examples of such use include The New Palgrave Dictionary of Economics

The New Palgrave Dictionary of Economics

The New Palgrave Dictionary of Economics , 2nd Edition, is an eight-volume reference work, edited by Steven N. Durlauf and Lawrence E. Blume. It contains 5.8 million words and spans 7,680 pages with 1,872 articles. Included are 1057 new articles and, from earlier, 80 essays that are designated as...

(2008, v. 8, Appendix IV, and online via (sub)category links) and National Bureau of Economic Research

National Bureau of Economic Research

The National Bureau of Economic Research is an American private nonprofit research organization "committed to undertaking and disseminating unbiased economic research among public policymakers, business professionals, and the academic community." The NBER is well known for providing start and end...

 Working Papers abstracts by year via JEL category links.

There are 19 main categories, each with multiple subcategories. Wikipedia categories used for articles in economics mostly follow the JEL classification codes. The primary codes are:
JEL: A - General Economics

Economics

Economics is the social science that analyzes the production, distribution, and consumption of goods and services. The term economics comes from the Ancient Greek from + , hence "rules of the house"...

 and Teaching

Economics education

Economics education or economic education is a field within economics that focuses on two main themes: 1) the current state of, and efforts to improve, the economics curriculum, materials and pedagogical techniques used to teach economics at all educational levels; and 2) research into the...

JEL: B - History of Economic Thought

History of economic thought

The history of economic thought deals with different thinkers and theories in the subject that became political economy and economics from the ancient world to the present day...

, Methodology

Economic methodology

Economic methodology is the study of methods, especially the scientific method, in relation to economics, including principles underlying economic reasoning...

, and Heterodox Approaches

Heterodox economics

"Heterodox economics" refers to approaches or to schools of economic thought that are considered outside of "mainstream economics". Mainstream economists sometimes assert that it has little or no influence on the vast majority of academic economists in the English speaking world. "Mainstream...

JEL: C - Mathematical and Quantitative Methods

Mathematical economics

Mathematical economics is the application of mathematical methods to represent economic theories and analyze problems posed in economics. It allows formulation and derivation of key relationships in a theory with clarity, generality, rigor, and simplicity...

JEL: D - Microeconomics

Microeconomics

Microeconomics is a branch of economics that studies the behavior of how the individual modern household and firms make decisions to allocate limited resources. Typically, it applies to markets where goods or services are being bought and sold...

JEL: E - Macroeconomics

Macroeconomics

Macroeconomics is a branch of economics dealing with the performance, structure, behavior, and decision-making of the whole economy. This includes a national, regional, or global economy...

 and Monetary Economics
JEL: F - International Economics

International economics

International economics is concerned with the effects upon economic activity of international differences in productive resources and consumer preferences and the institutions that affect them...

JEL: G - Financial Economics

Financial economics

Financial Economics is the branch of economics concerned with "the allocation and deployment of economic resources, both spatially and across time, in an uncertain environment"....

JEL: H - Public Economics
JEL: I - Health

Health economics

Health economics is a branch of economics concerned with issues related to efficiency, effectiveness, value and behavior in the production and consumption of health and health care...

, Education

Education economics

Education economics or the economics of education is the study of economic issues relating to education, including the demand for education and the financing and provision of education...

, and Welfare
JEL: J - Labor

Labour economics

Labor economics seeks to understand the functioning and dynamics of the market for labor. Labor markets function through the interaction of workers and employers...

 and Demographic Economics

Demographic economics

Demographic economics or population economics is the application of economics to demography, the study of human populations, including size, growth, density, distribution, and vital statistics.Analysis includes economic determinants and consequences of:...

JEL: K - Law and Economics

Law and economics

The economic analysis of law is an analysis of law applying methods of economics. Economic concepts are used to explain the effects of laws, to assess which legal rules are economically efficient, and to predict which legal rules will be promulgated.-Relationship to other disciplines and...

JEL: L - Industrial Organization

Industrial organization

Industrial organization is the field of economics that builds on the theory of the firm in examining the structure of, and boundaries between, firms and markets....

JEL: M - Business Administration and Business Economics

Business economics

Business economics as a field in applied economics uses economic theory and quantitative methods to analyze business enterprises and the factors contributing to the diversity of organizational structures and the relationships of firms with labour, capital and product markets...

; Marketing

Marketing

Marketing is the process used to determine what products or services may be of interest to customers, and the strategy to use in sales, communications and business development. It generates the strategy that underlies sales techniques, business communication, and business developments...

; Accounting
JEL: N - Economic History

Economic history

Economic history is the study of economies or economic phenomena in the past. Analysis in economic history is undertaken using a combination of historical methods, statistical methods and by applying economic theory to historical situations and institutions...

JEL: O - Economic Development

Economic development

Economic development generally refers to the sustained, concerted actions of policymakers and communities that promote the standard of living and economic health of a specific area...

, Technological Change, and Growth

Economic growth

In economics, economic growth is defined as the increasing capacity of the economy to satisfy the wants of goods and services of the members of society. Economic growth is enabled by increases in productivity, which lowers the inputs for a given amount of output. Lowered costs increase demand...

JEL: P - Economic Systems
JEL: Q - Agricultural

Agricultural economics

Agricultural economics originally applied the principles of economics to the production of crops and livestock — a discipline known as agronomics. Agronomics was a branch of economics that specifically dealt with land usage. It focused on maximizing the crop yield while maintaining a good soil...

 and Natural Resource Economics

Natural resource economics

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; Environmental

Environmental economics

Environmental economics is a subfield of economics concerned with environmental issues. Quoting from the National Bureau of Economic Research Environmental Economics program:...

 and Ecological Economics

Ecological economics

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JEL: R - Urban

Urban economics

Urban economics is broadly the economic study of urban areas; as such, it involves using the tools of economics to analyze urban issues such as crime, education, public transit, housing, and local government finance...

, Rural

Rural economics

Rural economics is the study of rural economies, including:* farm and non-farm industry.* economic growth, development, and change * size and spatial distribution of production and household units and interregional trade* land use...

, and Regional Economics
JEL: Y - Miscellaneous Categories
JEL: Z - Other Special Topics