Unhelpfully translates to “suffering” but is better understood as the unreliability of those things that make us happy. Satisfaction is fleeting and is soon followed, or even accompanied, by dissatisfaction.
The term for ethics in Buddhism, it is one of the three foundational practices.
Two aspects of sīla are essential to the training: right “performance” (caritta), and right “avoidance” (varitta).
Understood as “emptiness” it is the notion that complexes have no inherent self and are only the formulation of other things. An example would be the field of light that receive through our eyes is then interpreted as an object which can be labeled. Another would be removing pieces from a car until the point at which it is no longer a car - the door is not a car, the wheels are not a car, but all of these things come together to form the concept of a car.