We can group worlds by size and composition.

There are different types of worlds

Giant rocky worlds (Theoretical).

Large Rocky worlds – Mercury, Venus, Earth and Mars.

Medium rocky worlds- Moon

Small rocky worlds- Asteroids and some moons like Phobos.

Water worlds (Theoretical).

Giant gas planets- Jupiter

Large gas planets Saturn.

Medium gas planets (or perhaps a cross between Gas Giants and terrestrial) – Uranus and Neptune.

Small gas planets (Theoretical)

Giant ice worlds (Theoretical – Earth size or larger)

Large Ice worlds – Titan, Ganymede, and many other large moons

Medium ice worlds- Pluto, Encaladus, Miranda and other moons

Small ice worlds- Comets, Kepler and Oort cloud objects