In order to better understand science, we need to understand the goals of science, and how those goals are achieved. The foremost goal of science is to understand and explain the natural world, and the phenomena that occur in the natural world. Now, science is distinguished from “non-science” by its use of the scientific method, which is a systematic approach to problem solving and explaining these phenomena that occur in the natural world.

So let’s look at the steps of the scientific method, and they we’ll look at each of these steps in greater detail. First, we make an observation, then we perform background research and form a hypothesis. Next we perform an experiment and analyze the results of the experiment, and draw conclusions based on those results. So let’s look at each of these steps in greater detail.

The first step is to make an observation. Now the observations that we make don’t need to be rigorous or have any pre-existing scientific evidence. It just needs to be a possible relationship or an odd phenomenon that you observe in the natural world. Observations generally connect two values to one another. For example, you may observe that salt seems to dissolve faster in warmer water than cooler water, so you’ve connected two values: one, the temperature of water, to another, how quickly salt dissolves.

The next step of the scientific method is to perform background research. Now when you perform background research, you want to learn all that you can about the topic, and to see if anyone has performed any experiments on this topic before. Now when you perform background research, you want to be sure that you’re using reliable sources, such as scientific journals or textbooks. Unreliable sources can not only provide you with incorrect information, but can often steer you in the wrong direction of how to do a good experiment.

The next step in the scientific method is to form a hypothesis. A hypothesis is an educated guess - based first on your observations, but also on the background research you performed - about the possible relationship that might exist. A hypothesis must be limited to one possible relationship. You want to define one correlation that might exist. And it must also be falsifiable, meaning that it can be disproven, or shown to be incorrect, based on an experiment.

Which brings us to the next step of the scientific method, performing an experiment. The experiment you perform must only test the relationship predicted in your hypothesis.

Sometimes it’s tempting, when you’re performing an experiment, to have the experiment cover a lot of different topics. So with the example given before, you might also want to test the effect that increasing the temperature of water has on how quickly sugar dissolves, or baking soda, but an experiment should only test one possible relationship, and that’s the relationship discussed specifically in your hypothesis. And your experiment should be designed so that your hypothesis is either supported or disproven by the results of the experiment. There should be no other option. When the experiment is done, you should be able to say either “the results of this experiment supported the hypothesis,” or “the results of this experiment did not support the hypothesis.”

When performing an experiment, we’re concerned about two values. The first is the independent variable, sometimes called the manipulated variable. This is the value that you change intentionally. All other input values should be controlled, that is to say kept constant. So with the example we’re discussing, the independent variable is the temperature of the water. We want to see if changing the temperature of the water affects how quickly salt dissolves, so the variable that we’re going to change is the temperature of the water. And the response variable, or dependent variable, is the that you are testing whether or not it changes in response to a change in the independent variable. So with this example, by increasing the temperature, we want to see what effect that has on how quickly salt dissolves. So the speed with which salt dissolves is our dependent variable. All other values should be kept constant in our experiment.

The next step in the scientific method is to analyze the results of our experiment. During your experiment, you must keep accurate, detailed, and honest records of what occurred during the experiment. If your records are not all three of these, then they are not valid, and they are not valuable. You’ll use tables, graphs, charts, to analyze and interpret the results of your experiment. Tables just present the data numerically, bur graphs and charts can make it easier to visualize possible relationships that exist between the independent variable and the dependent variable.

The last step of the scientific method is to draw conclusions. You’ll want to determine whether or not your hypothesis was supported by the results of your experiment. Now, if your hypothesis is not supported by the results of your experiment, that is still a good and valid result, and it still needs to be published and shared with the world. It needs to enter into the body of scientific knowledge, because – just like when you did background research for your experiment – other scientists are going to do background research for their experiments, and will need to see which experiments provided null results, or where the hypothesis was not supported.

Now, as your experiment enter into the body of scientific knowledge, it becomes incorporated into scientific theory. Now, we need to distinguish between a scientific theory and a scientific law. A scientific theory combines years of results of scientific experiments, and combines them into an explanation of how a certain phenomenon occurs. And that’s the operative word here: how. By contrast, a scientific law is just a description, usually in the form of a mathematical equation, of a natural process. Scientific laws do not describe how something happens, that falls under scientific theory. Scientific theories build on all the results of scientific experiments, and incorporate them into explanatory models that we can use to better understand the natural world.