What are data?

What are data?

Data are observations of a population or process. We may not be able to view the entire population or understand the whole process, but we can take measurements from them. These measurements are data. In their rawest form, data may be numbers, text, images, audio, and/or figures, to give some examples. For instance, if one wants to estimate the wind power resource in an area, they would deploy a limited set of sensors (anemometers) to measure wind speed, reported as numbers over time. Another classic example comes from political elections: it is impractical to survey the entire population of a country ahead of an election to find their position on the candidates, so polls are conducted on a sample of people from the population. The data measured here may be in text form, such as whether they "strongly agree" or "strongly disagree" with a candidate's position on a topic.