Anatta; not-self, that there is no such thing as a permanent self or soul, in that we are constantly changing and evolving
Anicca; all things and experiences are inconstant, unsteady and impermanent, everything is in constant flux. Things are constantly coming into being and ceasing to be. Nothing lasts.
Dukkha; suffering as a fundamental and unavoidable aspect of existence, which stems from clinging to impermanent things, craving pleasure, and wishing to avoid pain.