To be considered a scientific theory, it must meet certain criteria:

1. Supported by empirical evidence: Theories are based on data and observations.
2. Testable and falsifiable: Theories can be tested and potentially disproven through experimentation.
3. Explains and predicts phenomena: Theories provide a clear explanation and prediction of the observed phenomena.
4. Parsimonious: Theories should be simple and elegant, avoiding unnecessary complexity.
5. Widely accepted: Theories are accepted by the scientific community after peer review and replication.

Examples of scientific theories include:

1. Evolution through natural selection
2. Atomic theory
3. Plate tectonics
4. Germ theory of disease
5. Quantum mechanics

Theories are not static; they evolve as new evidence emerges, and they can be refined or even replaced if necessary.