How is evolution both fact and theory?

In science, the process of creating a concept or model of how the world functions begins with the development of a "hypothesis," which is based on the best available evidence and still requires testing by other scientists. These scientists attempt to "falsify" a hypothesis that is put forth and frequently attempt to float their own hypothesis; however, if a hypothesis is not falsified—that is, if no one can find a fatal flaw in it—it becomes a "theory," which is typically extremely well tested and effectively becomes the best explanation available at the moment for how the world functions. This is not the same as the term "theory"

When theories find their way into college and high school textbooks, they are essentially "facts" or theories that have never been refuted, even though scientists are frequently very hesitant to call anything a "fact" because science is always open to new, more accurate explanations.

Large-scale theories that are developed, such as plate tectonics, evolution, or the Big Bang, are sometimes referred to as "paradigms".

In other words, nothing in biology makes sense without evolution. Darwinian evolution has never been "falsified" at its core, making it both a "Theory" and essentially a biological fact. This is according to a well-known biologist.

Evolution is a fact in the sense that organisms have changed, or evolved, over time. The theory of evolution explains how this process occurs through mechanisms such as natural selection, genetic drift, and mutation. So, while the fact of evolution is the observed phenomenon of change in organisms over time, the theory of evolution is the scientific explanation for how and why this change occurs.