A scientist is anyone who is studying or has knowledge about the natural or physical sciences.

This can mean people who do chemistry, or biology, or psychology, or earth science like geologists! There are many fields of science. Scientists usually like to do research, which means studying and doing tests so that they can establish facts and find out new things!

Scientists are amazing because they help us find out more about the world we live in. Medical scientists help us learn more about the human body so that we can cure disease! Environmental scientists help us learn about the earth so that we can take better care of it. Scientists truly make the world a better place.

Scientists do all sorts of things. Some of us do experiments in a laboratory, to learn about useful and/or interesting things. Some of us think about things and try to figure out the answers, and what experiments people might do to find the answers. Scientists have given us so many things that we enjoy every day. Look around you and see your electric lights, refrigerator, computer, my cute little toy that changes color as the color of the light changes, my medicines, my clothes that are good for keeping me warm without making me sweaty, and lots more. All those things started with scientific discoveries.

We like to do science, and sometimes we get paid to do science. You do a science experiment when you try to figure out if it's cold enough to need a jacket. You can go outside and feel the air - that's an experiment. Or you can look at an outdoor thermometer - that's getting information to help you decide. Scientists call that information 'data.'

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Scientists use scales, rulers, thermometers, and lots of other tools to measure things. Scientists communicate their findings. We always want scientists to talk about their discoveries and share with others. They can tell other scientists, or they can tell people like you and me. Jul 5, 2016 from this source.

Scientists are people who try to understand the universe by looking at it, measuring it, and testing our ideas against what we see and what we measure. We do this because we are curious, yet skeptical - we do not accept an answer until we know that it is true, and the only way to know for a fact that something is true is by testing it.

There are many kinds of scientists, but in general we try to figure out how and why things happen in the world!

Usually this is done by running experiments, or making models. Scientists like to use what we call the “scientific method”. First, you make a hypothesis about what is going to happen. Hypothesis is just a fancy word for an educated guess. Based on what you already know you try to guess what will happen. Then you design an experiment where you will be able to see what happens. Next, you do the experiment and collect data - that is you write down what happens. Finally, you compare the results of the experiment (what happened) with your hypothesis. If they are the same that’s good! It means what you thought might be right. If they are not the same you go back and make another hypothesis based on your new information.

We do all this because we want to better understand our planet and our universe. There are many branches of science, but in general they fall under a few categories: biology (the study of life and living things), chemistry (the study of matter or chemicals and their properties and behavior), and physics (the study of matter and its motion and behavior through space and time). Of course, many subjects may fall into multiple categories - for example biochemistry combines biology and chemistry!