Three characteristics

The three characteristics of experience, also often referred to as the three marks of existence, include 1) Suffering or dukkha 2) Impermanence or anicca & 3) No-self or annatta

These three characteristics, when tuned into directly through vipassana techniques or other techniques, lead to direct insights into the nature of things. As such they are the fodder and basis for the progress of insight and lead directly to enlightenment, awakening, or fundamental wisdom.