Physics is the natural science that studies matter, energy, space, and time—and the forces and interactions that connect them. Its goal is to understand how the universe behaves at all scales, from tiny subatomic particles to huge galaxies, by uncovering the fundamental rules that describe nature.

Key ideas:
- It seeks simple, universal laws and uses math to describe and predict how systems behave.
- It relies on observation, experiments, and theories tested against evidence (the scientific method).
- It covers both classical physics (everyday phenomena like motion, forces, light, heat, and electricity) and modern physics (quantum mechanics and relativity), along with many specialized fields (astrophysics, particle physics, condensed matter, etc.).

Why it matters:
- Physics explains why things happen and provides the foundation for much of technology and everyday life (electricity, computers, medical imaging, GPS, lasers, etc.).

If you’d like, I can give a simple example (like how Newton’s laws govern motion) or dive into a specific area you’re curious about.