* Physics: The study of matter and its motion through space and time, along with related concepts such as energy and force. It is the most fundamental of the natural sciences.

* Chemistry: The study of matter and its properties as well as how matter changes. It explores the composition, structure, properties, and reactions of matter.

While these are the two main branches, you can find further subdivisions within each:

Within Physics:

* Mechanics: Deals with the motion of objects.

* Thermodynamics: Studies heat and its relation to energy.

* Electromagnetism: Studies electricity and magnetism.

* Optics: Studies light and its behavior.

* Nuclear physics: Studies the atom's nucleus.

* Astrophysics: Studies celestial objects and phenomena.

Within Chemistry:

* Organic chemistry: Studies carbon-containing compounds.

* Inorganic chemistry: Studies compounds that do not contain carbon.

* Analytical chemistry: Studies the composition and structure of matter.

* Physical chemistry: Studies the physical principles behind chemical reactions.

* Biochemistry: Studies the chemical processes of living organisms.

It's important to remember that the boundaries between these branches are not always clear-cut, and many areas of study involve overlap and interdisciplinary approaches.