So the parameter would be for the entire population. If it was possible, you would go talk to every, maybe there's a million people in the city, you would talk to all million of those people, and ask them how much time they spend on a computer, and you would get the average, and then that would be the parameter. So population parameter, would be average time on a computer per day. Average daily time on a computer. Now you determine that it's impractical to go talk to everyone, so you're not going to be able to figure out the exact population parameter, average daily time on a computer, so instead you do a sample study. You randomly sample, and there's a lot of thought in thinking about whether your sample is truly random, so you randomly sample, but there's also different techniques of randomly sampling. So you randomly sample people from your population, and then you take the average daily time on a computer for your sample, and that is going to be an estimate for the population parameter.