Suffering, agony, or pain in a broad sense, may be an experience of unpleasantness or aversion, possibly associated with the perception of harm or threat of harm in an individual. Suffering is the basic element that makes up the negative valence of affective phenomena. The opposite of suffering is pleasure or happiness.

Affect, in psychology, refers to the underlying experience of feeling, emotion, attachment, or mood. In psychology, "affect" refers to the experience of feeling or emotion. It encompasses a wide range of emotional states and can be positive or negative. Affect is a fundamental aspect of human experience and plays a central role in many psychological theories and studies. It can be understood as a combination of three components: emotion, mood, and affectivity. In psychology, the term "affect" is often used interchangeably with several related terms and concepts, though each term may have slightly different nuances. These terms encompass: emotion, feeling, mood, emotional state, sentiment, affective state, emotional response, affective reactivity, disposition. Researchers and psychologists may employ specific terms based on their focus and the context of their work.