Purpose of Interview

During an interview there can be a variety of different purposes as to why the interview is taking place. Also you can also receive a lot of information on a topic. So this means that a lot of different interview techniques can be used in the interview to extract the information that you want out of your interviewee.
Purpose of Interviews

• Research 
• Understanding
• Inform
• Interpretive
• Emotional

Research 
A research interview an interview which takes place so that you can get the interviewees knowledge about the topic that is being discussed as usually the person who you are interviewing is an expert in the field you are asking about.

Understanding
This type of interview most likely takes place to increase the audience's awareness on the issue and certain topic or topics that are being spoken about.

http://news.bbc.co.uk/1/hi/programmes/newsnight/newsnight_interviews/default.stm

Inform 
This type of interview is used for the purpose of sharing information with the audience
https://www.youtube.com/watch?v=2tHrUr_ozZs 
The interview above is informative as it gives you some back ground information on guardians of the Galaxy and what it was like to film. It also gives information on the television show parks and recreation. It also informs people all about the film which could encourage them to watch it. 
Interpretive 
This purpose of interview is used to express or explain someone's certain opinion to the audience.
https://www.youtube.com/watch?v=KzYJccxLSFA 
The interview above between Bear Gryills and Piers Morgan's is interpretive as it shows the audience  Bear Gryills friends and wife's opinion on him. By it being this type of interview it allows the audience into Bar Gryills life to find out more about him and help them to understand him more.


Emotional
This interview purpose is used to be able to get the audience to see the story or situation from someone else's point of view. These interviews would be more personal due to the topic that is being spoken about and they would also likely be informal as they need the interviewee to open up and answer the questions.
https://www.youtube.com/watch?v=2BWs6T3HjhU 
This is an emotional interview above because it allows the audience to see how Angelia Jolie feels about a certain topic and issue. This type of interview allows the audience to see how she feels about what she went through. This also helps the viewers to know more in-depth about what happened.