The number of children in their class who prefer apples to oranges, how a stain responds to a cleaner and the inches a tomato plant grew when they were watered with lemonade are examples of data. The facts, observations or statistics assembled for analysis represent data. At a science fair, data is the answer to the question you asked when you made a hypothesis. If you are not sure about the methods for the science fair, ask for help from your teacher.
Two types of data
The data are generally divided into two categories: quantitative and qualitative. The numerical information that is measured with tools such as a ruler or graduated cylinder is quantitative information. For example, you can measure the amount of rainfall in a month or determine how much a plant grew when it is kept in a dark room. Qualitative data imply the appearance, taste, smell, texture or sound of something described with words. When you see that ketchup leaves a darker stain than mustard on a white shirt, it is collecting qualitative data.