The Four Known Fundamental Interactions

Electromagentism
Causes interaction between electrically charged particles
in areas called electromagnetic fields

And binds (negative) electrons to (positive) protons

which together form atoms
which together form molecules
which are categorized as elements
which together form chemicals
which together form everything we see

A changing electric field generates a magnetic field

and vice-versa
in a process called electromagnetic induction

Strong Interaction
Causes the (netural) neutrons to bind to the (positive) protons and form the nucleus

and quarks to bind to gluons and form nucleons, etc
overriding electromagnetism
The strongest of the Interactions

Weak Interaction
Causes radioactivity through beta decay
(the emission of electrons by neutrons or positrons by the protons in atomic nuclei)

And is due to the exchange of the heavy W and Z bosons



Gravitation
Causes dispersed matter to coalesce

And is due to the curvature of spacetime which governs the motion of inertial objects

Newton's simpler, still reliable theory states:

I deduced that the forces which keep the planets in their orbs must [be] reciprocally as the squares of their distances from the centers about which they revolve: and thereby compared the force requisite to keep the Moon in her Orb with the force of gravity at the surface of the Earth; and found them answer pretty nearly.