Interest questionnaires ask you questions about what activities you most enjoy doing and what type of work you might prefer.
The questions could be presented as words, sentences or even pictures. In most cases you would have to rate yourself of say which activities you prefer most and which you like least.
These tests are often used to guide people in the choice of subjects to study, or to help them make a career choice. Because these tests are used to make important decisions about a person's future, the consequences of making a mistake and giving the wrong advice could be serious. A person might spend years studying unsuitable subjects. spend a lot of money learning the wrong things, or enter a career that is not suited to them and spend years being unhappy in their work.
Interest questionnaires are reserved by law for registered psychology professionals.