There are two main types of information that you can get from research that involves people: subjective and objective.
The word “subjective” means that it is an opinion, or a memory, or your impression of something. The feeling it gives you. The expectations it creates. Not a fact.
i.e. — There is no right answer.
To get subjective information you have to ask people questions.
The word “objective” means a fact. Something you can prove. Your opinion doesn’t change it, no matter how hard you wish.
If people had perfect memories and never lied (especially to themselves) we could ask them about this stuff. Hence, objective data comes in the form of measurements and statistics. But just because you can count something doesn’t make it objective.
For example: If 102 people say something is good and 50 people say it’s bad, the only objective information you have is the number of people that voted. Whether it is “good” or “bad” is still subjective.
As a general rule, more people makes more reliable information, even if it is subjective. One opinion could be completely wrong. If a million people agree, it is a good representation of the crowd’s beliefs (but could still be false, objectively). So collect as much info as possible for your research.
Lots of subjective info can become… almost objective?
If you ask a lot of people to guess the answer to something objective — like jelly beans in a jar — the average guess will often be pretty close to the real, objective, answer.
There are 3 basic types of questions:
Open Questions — “How would you describe me?” — This allows for a wide range of answers, and works well when you want all the feedback you can get.
Leading Questions — “What are this site's most useful features?” — This narrows the answers to a certain type. My example assumes that the site has useful features which might not be true! Be careful: this type of question also excludes answers you might want to know!
Closed/Direct Questions — “Which is more useful, site A or site B?” — This type of question offers a choice. Yes or no. This or that.
Remember, always ask Open Questions in your User Research, and avoid the other two types.