A job interview is an opportunity to learn critical information about potential employees, but the information you get is only as good as the questions you give. The key to giving good questions is delivery of a variety of question types. Ask fact-based, open-ended, situational and behavioral questions to get a well-rounded picture of your potential employee.
Give the interviewee fact-based questions to get specific information such as her education or past experience. For example, you might ask, "What is your highest level of education?" These questions are simple and should be evaluated based on the content of the response.
Ask open-ended questions to learn more about the interviewee without guiding her response. Open-ended questions allow the interviewee to tell you things that you might not think to ask. You might, for example, say, "Tell me about your past work experience."
Give the interviewee situational questions to see how she would respond to a particular situation. You might, for instance, ask "If you were asked to design our new advertising campaign, how would you approach it?" This allows you to see how the interviewee might handle real tasks that you would assign her.
Ask behavioral questions to get a sense of how the interviewee has performed in the past. An example is asking the interviewee to tell you about a time when she felt challenged and how she approached this challenge. This gives you the opportunity to understand how she has reacted in real-life situations.