There are different user research tools and methodologies to help you to better understand the users and their needs, such as quantitative and qualitative research, contextual inquiry, observation, netnography, user interview, surveys, card sorting, tree testing, A/B testing, diary studies, data analysis, eye tracking, and so on. Which one (or ones) you will you use depends on what you are trying to achieve and what you are looking for.
To help you to decide when to use which method, you can consider using a three-dimensional framework with the following axes:
- Qualitative versus quantitative
- Attitudinal versus behavioral
- Context of use