The following is presented as an overview of and topical guide to physical science:

Physical science – encompasses the branches of natural science and science that study non-living systems, in contrast to the life sciences. However, the term "physical" creates an unintended, somewhat arbitrary distinction, since many branches of physical science also study biological phenomena.

The foundations of the physical sciences rests upon key concepts and theories, each of which explains and/or models a particular aspect of the behavior of nature.

Physics is the "fundamental science" because the other natural sciences (biology, chemistry, geology, etc.) deal with systems that obey the laws of physics. The physical laws of matter, energy, and the forces of nature govern the interactions between particles (such as molecules, atoms, or subatomic particles). Some basic parts of physics are:

Chemistry, built upon physical concepts, addresses phenomena associated with the structure, composition and energetics of matter and the changes it undergoes. Often known as the central science, chemistry connects the fundamental laws of physics to engineering and other natural sciences such as biology, earth science, astronomy and material science

A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that provide mechanical advantage (also called leverage).

Usually the term refers to the six classical simple machines which were defined by Renaissance scientists:

A simple machine is an elementary device that has a specific movement (often called a mechanism), which can be combined with other devices and movements to form a machine. Thus simple machines are considered to be the "building blocks" of more complicated machines. This analytical view of machines as decomposable into simple machines first arose in the Renaissance as a neoclassical amplification of ancient Greek texts on technology, and is still a central part of engineering in today's age of applied science. For example, wheels, levers, and pulleys are all used in the mechanism of a bicycle. Between the simple machines and complex assemblies, several intermediate classes can be defined, which may be termed "compound machines" or "machine elements". The mechanical advantage of a compound machine is simply the product of the mechanical advantages of the simple machines of which it is composed.