A well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.

Here's a breakdown of what makes a scientific theory:

* Well-substantiated: It's supported by a large body of evidence from multiple sources, including experiments, observations, and data analysis.

* Explanation: It provides a coherent and consistent framework for understanding a phenomenon, rather than simply describing it.

* Aspect of the natural world: It deals with things that can be observed and measured, not with subjective opinions or beliefs.

* Incorporates facts, laws, inferences, and tested hypotheses: It draws upon established scientific knowledge and integrates it into a cohesive whole.

Key points to remember:

* Scientific theories are not guesses or hunches. They are carefully constructed explanations backed by evidence.

* Theories can be modified or replaced as new evidence emerges. This is a strength of science, as it allows for progress and refinement of our understanding.

* Theories are different from scientific laws. Laws describe patterns in nature, while theories explain why those patterns exist.

Examples of scientific theories:

* Theory of Evolution: Explains the diversity of life on Earth through descent with modification.

* Theory of Plate Tectonics: Explains the movement of Earth's crust and the formation of continents and oceans.

* Theory of Relativity: Explains the relationship between space, time, gravity, and matter.

By understanding these key points, you can appreciate the power and importance of scientific theories in our quest to understand the universe.