Research drives progress. From the rapid development of COVID-19 vaccines in 2020 to the steady accumulation of climate data over the past two decades, systematic inquiry shapes how societies solve problems, innovate, and make decisions. In the 21st century, understanding different types of research has become essential for students, professionals, and organizations alike.
When people talk about “types of research,” they often mean different things. Some refer to broad purposes—like basic versus applied research. Others focus on specific designs such as experimental, longitudinal, or case studies. This article will clarify both perspectives, giving you a comprehensive framework for understanding how researchers approach questions across scientific and nonscientific fields.
We’ll start by outlining the major categories so you get answers early. Then we’ll dive deeper into key methods with concrete examples from healthcare, education, business, and the social sciences. Whether you’re designing a thesis, evaluating market trends, or assessing a public policy, understanding research types helps you choose the right approach and interpret findings critically.
What this article covers:
Core purposes: basic (fundamental) research vs. applied research
Major methodological families: qualitative, quantitative, and mixed methods
Common designs by time, setting, and structure
Specialized types including exploratory, causal, action, and historical research
How to choose the right type for your project
Core purposes of research: basic vs. applied
The “purpose” of research answers a simple question: why is this study being done? Many frameworks begin by distinguishing between basic research (pursuing knowledge for its own sake) and applied research (solving practical problems). These purposes cut across disciplines—from physics to sociology to marketing—and across time periods.
Consider how purpose influences funding. Government agencies like the National Science Foundation often support basic research that may not have immediate application, while corporations tend to invest in applied research with measurable outcomes. Understanding this distinction helps you position your own projects and evaluate evidence from others.
The subsections below contrast fundamental versus applied research, as well as theoretical versus experimental approaches. These categories aren’t mutually exclusive; many projects blend elements of each.
Fundamental (basic) vs. applied research
Fundamental research, also called basic research or pure research, aims to expand general knowledge without targeting immediate commercial or practical application. Researchers pursue questions because they’re intellectually compelling, not because the answers will solve a specific problem tomorrow.
Examples of basic research:
CERN’s particle physics experiments in the 2010s exploring the nature of matter
Early DNA structure research by Watson and Crick in the 1950s
Studies on black hole formation and behavior
Investigations into how children naturally acquire language
This type of theoretical research typically takes place in universities and research institutes, where scientists have freedom to follow curiosity-driven questions.
Applied research, by contrast, focuses on solving concrete, often time-bound problems. Researchers work backward from a practical problem to find solutions that can be implemented.
Examples of applied research:
Testing a new diabetes medication in clinical trials during 2022
Optimizing e-commerce checkout conversion rates for a retail company
Designing an evidence-based reading program for elementary students
Evaluating a new climate policy’s impact on carbon emissions
Applied research happens in industry R&D labs, government agencies, NGOs, and consulting firms—anywhere that solving problems drives the work.
Basic and applied research feed into each other. The mRNA platform technology that enabled rapid COVID-19 vaccine development in 2020 emerged from decades of fundamental research on messenger RNA. Without that basic science foundation, applied vaccine development wouldn’t have been possible.
Theoretical vs. experimental research
Theoretical research develops, refines, or critiques models and concepts rather than collecting new empirical data. It’s the work of building frameworks that explain how the world works.
Examples of theoretical research:
Constructing mathematical models for disease spread (SIR models) used in epidemiology
Developing communication theories about social media echo chambers
Proposing new algorithms in computer science before implementation
Economic growth theories like Solow’s model from the 1950s and its modern extensions
Experimental research, by contrast, involves manipulating one or more independent variables under controlled conditions to observe effects on dependent variables. The researcher introduces changes and measures outcomes.
Examples of experimental studies:
A clinical trial comparing two hypertension medications with random assignment to control groups
A psychology study testing how sleep deprivation affects memory
An A/B test measuring click-through rates on different website button designs
Voter turnout experiments testing different mobilization messages
The relationship between these approaches is cyclical. Theoretical research generates predictions and hypotheses. Experimental research tests those predictions with real-world or lab data. Results then inform refinements to theory.
Both types appear across disciplines. Political scientists run experiments on voter behavior. Media researchers test hypotheses about exposure to misinformation. Education researchers test hypothesis about teaching methods in classroom settings.
Major methodological families: qualitative, quantitative, and mixed methods
Research methodology describes how data are collected and analyzed to answer questions. The three major methodological families—qualitative, quantitative, and mixed methods, represent fundamentally different approaches to understanding the world, and comprehensive user research methods guides to qualitative and quantitative techniques show how these are applied in practice.
Qualitative research focuses on meanings, experiences, and context through non numerical data. Quantitative research emphasizes numerical data and statistical analysis to test hypotheses. Mixed methods research combines both approaches for a more complete understanding, and understanding the key differences between qualitative and quantitative research helps you choose appropriately. .
From the 1990s onward, mixed methods designs became increasingly prominent in education, health services, and social research as researchers recognized the limitations of single-method approaches. Today, choosing among these families depends primarily on your research questions. “Why do customers churn?” calls for qualitative methods, and user research guides that explain how to choose and apply the right method can help frame that inquiry. “What percentage churn each year?” requires quantitative methods.
Qualitative research
Qualitative research collects and interprets non numerical data to explore the “why” and “how” of human behavior. Instead of counting occurrences or measuring variables, researchers examine words, images, observations, and narratives to understand meanings and experiences, often using expert interview techniques for qualitative research alongside qualitative researchmethods implementation guides that emphasize rigorous, systematic collection and analysis. .
Common qualitative research methods include:
Concrete examples:
A 2021 UX study observed users interacting with a mobile banking app, coding qualitativedata through thematic analysis about where they hesitated or expressed confusion, similar to qualitative research in product development that uncovers usability issues and unmet needs and is further detailed in UX research guides covering methods, best practices, and applications. An ethnographic study examined remote work culture after 2020 by embedding researchers in virtual teams. Healthcare researchers conducted interviews with patients about telehealth experiences to understand barriers to adoption. .
Qualitative methods excel at generating rich detail and context-sensitive findings. They’re ideal for studying new or sensitive topics where existing theory is limited. However, qualitative research typically uses small sample sizes (often 5-50 participants) selected through purposeful sampling rather than random selection. This means findings may not generalize to larger populations.
Major fields using qualitative methods include sociology, anthropology, education, healthcare quality improvement, product and UX research, and marketing insights work focused on better understanding customer motivations by asking qualitative research questions for user research, conducting structured user interviews with clear goals and guides, and analyzing qualitative researchdata for product decisions. .
Quantitative research
Quantitative research systematically collects and analyzes numerical data to test hypotheses, estimate parameters, and identify patterns across populations. It seeks measurable outcomes and statistical precision, particularly in quantitative researchmethods that rely on structured surveys and large samples and in comparative guides to quantitative vs qualitative research. .
Key quantitative designs include:
Surveys with closed-ended questions (such as Likert scale response options) that follow effective survey methodology principles)
Experiments with random assignment to treatment and control groups
Quasi-experiments when random assignment isn’t possible
Structured observations where behaviors are counted and categorized
Analysis of existing quantitative data like financial reports or census records
Example studies:
A national health survey measures obesity rates across population characteristics like age, income, and region, relying on rigorous survey design and question formulation to ensure valid results. An e-commerce company runs an experiment testing click-through rates of three advertisement designs. A real estate analyst examines a 10-year dataset analyzing housing prices and their relationship to two or more variables like interest rates and employment levels.
Quantitative research relies on statistical analysis tools: t-tests, ANOVA, regression, correlation, often implemented in software like R, Python, or SPSS. Results appear as graphs, tables, percentages, and confidence intervals. Large sample sizes (often 100-1000+ participants via random sampling) enable researchers to generalize findings to larger populations.
The strengths of quantitative methods include objectivity, statistical power, and the ability to quantify effect sizes with precision. Limitations include potential oversimplification of complex concepts and missing contextual nuances that numbers can’t capture.
Mixed-methods research
Mixed methods research intentionally integrates qualitative and quantitative approaches in a single project to gain a more complete understanding of research questions. It’s not simply doing both types separately; it’s deliberately combining them to leverage the strengths of each, as in mixed methodsresearch guides to combining qual and quant data. .
Common mixed-methods designs:
The mixed methods approach combines qualitative and quantitative research designs to provide comprehensive insights. One common design is the sequential exploratory design, where researchers start with qualitative methods, such as interviewing customers to understand their pain points, and then follow up with quantitative surveys to assess how frequently those issues occur across a larger sample. Another design is sequential explanatory, which begins with quantitative data collection and analysis to identify patterns, followed by qualitative interviews to explore why those patterns exist. Concurrent designs involve collecting both qualitative and quantitative data simultaneously, such as administering surveys while conducting focus groups.
Real-world examples illustrate the effectiveness of mixed methods. For instance, a public health agency might evaluate a smoking cessation campaign by combining survey statistics on quit rates with focus group feedback about which messages resonated with participants. Similarly, a university assessing a new advising program could use enrollment data alongside student interviews to gain a fuller understanding of the program's impact. In business, a company might examine relationships between employee engagement scores and themes emerging from qualitative exit interviews. This approach allows for triangulating findings, explaining unexpected numerical results with qualitative depth, and creating richer narratives for stakeholders.
While mixed methods research offers robust insights, it also poses challenges. It can be more time consuming and costly due to the need for diverse methodological skills and managing multiple data types. However, for complex research problems that require understanding both “how many” and “why” questions, the mixed methods approach often produces the most actionable insights.
A public health agency evaluates a smoking cessation campaign by combining survey statistics on quit rates with focus group feedback about what messages resonated. A university assesses a new advising program using enrollment data plus student interviews about their experiences. A company examines relationships between employee engagement scores and qualitative exit interview themes.
The mixed methods approach is useful for triangulating findings (checking if different methods reach similar conclusions), explaining surprising numerical results with qualitative depth, and creating richer stories for stakeholders who need both data and narrative.
Challenges include increased time and cost, plus the need for research teams with diverse methodological skills. Not every project warrants this complexity, but for complex research problems spanning both “how many” and “why” questions, mixed methods often produce the most actionable insights.
Common research designs by time, setting, and structure
Beyond purpose and methodology, research can be classified by time frame (cross-sectional vs. longitudinal), setting (field vs. laboratory), and flexibility (fixed vs. flexible designs). These classifications help structure projects across business, education, public health, and technology evaluation and are central to any research design framework for planning studies, particularly in market research resource hubs that cover tools, methodologies, and strategy.
Marketers choosing between a one-time customer survey and a multi-year tracking study face a time frame decision, especially when planning step-by-step market research projects that combine primary and secondary methods. HR teams deciding whether to conduct engagement research in actual workplaces or controlled interview rooms face a setting decision. Policy analysts choosing between a pre-designed survey and an evolving interview study face a flexibility decision.
The following subsections cover widely referenced designs and when to use each. Your choice depends on your timeline, budget, control requirements, and the nature of your research problem.
Cross-sectional and longitudinal research
Cross-sectional research studies a population or sample at a single point in time. Think of it as a snapshot capturing how things look right now.
Cross-sectional examples:
A 2024 survey of customer satisfaction across regions
Comparing attitudes toward remote work among employees of different ages in one survey
Analyzing income levels in different cities within a single fiscal year
A market study examining brand awareness across demographic segments
Cross-sectional designs are faster and less expensive than alternatives. They’re excellent for benchmarking and describing current conditions. However, they can’t show how things change over time or establish temporal sequences needed for causal claims.
Longitudinal research follows the same individuals, groups, or entities over multiple time points, months, years, or even decades. It tracks the same sample across waves of data collection.
Longitudinal examples:
A 5-year study tracking career paths of 2020 university graduates
The Framingham Heart Study, which began in 1948 and continues today, examining cardiovascular disease risk factors
A company tracking the same cohort of employees’ engagement scores annually
Longitudinal studies examining student achievement from elementary through high school
Longitudinal research reveals trends, developmental patterns, and possible causal directions. If you measure A before B consistently occurs, you have stronger evidence that A might influence B. The trade-offs include participant attrition (people drop out over time), higher costs, and longer timelines before results emerge.
Choose cross-sectional when you need a quick snapshot or benchmark. Choose longitudinal when you need to track change over time or when uncovering patterns of development is central to your research questions.
Field research vs. laboratory research
Field research collects data in natural environments where participants live, work, or interact. The researcher enters the real world rather than bringing participants to a controlled space.
Field research examples:
Observing classroom interactions in a primary school
Measuring air quality near a manufacturing plant
Shadowing nurses during hospital shifts to understand workflow
Conducting ethnographic research in online communities
Studying consumer behavior in actual retail stores
Field settings offer ecological validity: findings reflect real-world conditions with all their complexity. You observe human behavior as it naturally occurs. The challenge is less control over variables and more “noise” in your data from factors you can’t manage.
Laboratory research occurs in highly controlled environments (scientific labs, usability testing rooms, simulation facilities) where conditions are carefully managed.
Laboratory research examples:
Testing a pharmaceutical compound’s effects under controlled clinical conditions
Running a psychology experiment on memory in a university lab
Conducting usability testing of a new app in a dedicated UX lab
Measuring physiological responses to stimuli in a controlled setting
Lab studies offer precision. You can isolate variables, control for confounds, and replicate conditions exactly. The trade-off is that findings may not fully represent everyday conditions. People behave differently when they know they’re being observed in a formal setting.
Most scientific research balances these considerations. Some questions demand lab precision; others require field realism. Many research designs combine both: developing interventions in lab settings, then testing them in field conditions.
Fixed vs. flexible research designs
Fixed research designs establish procedures, instruments, and variables before data collection begins. Everything is pre-planned and standardized.
Fixed design examples:
A randomized controlled trial following a predetermined protocol for a new therapy
A market segmentation survey with pretested questions administered in Q2 2025
An experimental correlational research study with defined measurement instruments
Annual employee surveys using identical questions year over year
Fixed designs enable high comparability across participants, easier replication, and straightforward statistical analysis. When research findings need to be compared across groups or time periods, standardization is essential.
Flexible research designs allow procedures and questions to evolve during data collection. They’re responsive to emerging insights.
Flexible design examples:
A case study where interview questions adapt as new themes emerge
Action research where a teacher iteratively adjusts methods across terms based on student responses
Grounded theory research that builds categories through constant comparison as data accumulates
Exploratory research in a new market where initial assumptions may prove wrong
Flexibility benefits studies of poorly understood topics, context-dependent phenomena, or situations requiring researcher responsiveness. The risk is bias if changes aren’t documented transparently. Every adaptation must be justified and recorded.
Choose fixed designs when you have clear hypotheses and need standardized measurement. Choose flexible designs when you’re exploring new territory and need room to follow unexpected leads.
Additional specialized types of research
Beyond the broad categories of purpose, methodology, and design structure, many textbooks and professional guides describe specialized types that serve particular aims. These labels often combine elements from earlier categories but highlight specific objectives common in business, education, and policy contexts, all of which presuppose careful research problem formulation using a clear methodology.
In practice, a single project may combine several of these types. An organization might begin with exploratory research to understand a problem, follow with descriptive research to document its scope, and conclude with causal research to test solutions, often drawing on comprehensive guides to market, product, and UX research methods and returning repeatedly to methodology guides for formulating research problems as their understanding evolves.
Exploratory, descriptive, and analytical research
Exploratory research is early-stage inquiry used when a research problem isn’t well defined. The goal is generating ideas, hypotheses, or questions rather than testing them, much like generative research methods used in product and UX design and exploratory user research for product managers seeking to reduce risk and uncover needs.
Exploratory examples:
Initial interviews with customers to understand why a product is underperforming
Literature reviews examining emerging AI regulations to identify research gaps
Scanning competitor websites and industry reports to find answers to preliminary questions
Pilot studies testing whether a research design is feasible
Exploratory work often uses qualitative methods—interviews, document screening, observations—because flexibility matters more than statistical precision at this stage.
Descriptive research documents characteristics of a population or phenomenon. It answers “what does it look like?” questions.
Descriptive examples:
Describing average commute times across a metropolitan area
Profiling users of a new mobile app by demographics and usage patterns
Summarizing population characteristics for a 2024 election poll
Counting word occurrences in media coverage to identify dominant themes
Content analysis categorizing types of
Conclusion
Understanding the different types of research is crucial for anyone involved in scientific and nonscientific fields. Whether your goal is to expand knowledge through fundamental research or solve practical problems with applied research, choosing the right research methodology enhances the quality and relevance of your findings. Qualitative, quantitative, and mixed methods approaches each offer unique strengths for collecting and analyzing data, uncovering patterns, and exploring cause and effect relationships.
Effective research requires careful consideration of the research problem, design, and ethical considerations, as well as strong research skills to navigate the research process successfully. By selecting appropriate methods and maintaining a clear focus on your research questions, you can generate new ideas, contribute meaningful insights, and support informed decision making across diverse disciplines.
Ultimately, mastering the various types of research empowers you to conduct rigorous studies that advance knowledge, influence policy, and address real-world challenges with confidence and clarity.