Or you can have an experiment. Experiment. So let's go through each of these, and always pause this video and see if you can think about what these words likely mean, or you might already know. Well, sample study we have looked at, this is really where you're trying to estimate the value of a parameter for a population. So what's an example of that? So let's say we take the population of people in a city, and so that could be hundreds of thousands of people, and the parameter that you care about is how much time, on average, do they spend on a computer. So the parameter would be for the entire population.