The nature around us is very colourful and diverse. Physics is the study of nature and its laws.
Physics is an experimental science: Physicists observe the phenomena of nature and try to find patterns that relate these phenomena. These patterns are called physical theories or when they are very well established and widely used, they are called physical laws or principles.
The meaning of the word “theory”: Calling an idea a theory does not mean that it’s just a random thought or an unproven concept. Rather, a theory is an explanation of natural phenomena based on observation and accepted fundamental principles. An example is the well-established theory of biological evolution, which is the result of extensive
research and observation by generations of biologists.
To develop a physical theory, a physicist has to learn to ask appropriate questions, design experiments to try to answer the questions and draw appropriate conclusions from the results.