A questionnaire to collect lots of data
Surveys have the goal to ask as many people as possible a certain amount of questions.
The people doing the survey should be end users or people from other target groups that are relevant to the project.
A survey can be made on paper, in person or online. All of these approaches have advantages and disadvantages but generally spoken online-surveys give many opportunities including the easier analysis of the data one the survey is closed.
A survey can contain multiple question types including multiple-choice, multiple-check where user can select multiple options or free-text-questions to give you some samples.
For UX Designers Likert Scales are very interesting as users position their opinion on a scale (e.g. 1-5) between to opposite words (e.g. intuitive vs. complex).
Also very interning for UX Designers are standardises questionnaires which are questionnaires that were developed and evaluated over time by multiple experts. Due to the evaluation and experience of the questionnaires their value is very high and it is possible to compare the own solution to others as the analysis of the collected data follows a structured process with every product, software or service.