A-to-Z, here is a list of favorite research methods and techniques I have experience with planning, executing, analyzing, and synthesizing:
Affinity Diagramming
Card Sorting
Cloze Testing
Competitor And Comparator Analysis
Concept Mapping
Content Inventory And Auditing
Contextual Inquiry
Design Workshops
Desirability Testing
First-Click Testing
Heuristic Evaluation
Impression Testing
Interviewing
Journey Mapping
Kano Analysis
Literature Reviews
Mental Model Diagramming
Rapid Iterative Testing And Evaluation
Surveys
Task Analysis
Tree Testing
Triading
Usability Testing
In-Person
Remote
