Aesthetics is the branch of philosophy that studies beauty, taste, and related phenomena. In a broad sense, it includes the philosophy of art, which examines the nature of art, artistic creativity, the meanings of artworks, and audience appreciation.

Aesthetic properties are features that influence the aesthetic appeal of objects. They include aesthetic values, which express positive or negative qualities, like the contrast between beauty and ugliness. Philosophers debate whether aesthetic properties have objective existence or depend on the subjective experiences of observers. According to a common view, aesthetic experiences are associated with disinterested pleasure detached from practical concerns. Taste is a subjective sensitivity to aesthetic qualities, and differences in taste can lead to disagreements about aesthetic judgments.

Artworks are artifacts or performances typically created by humans, encompassing diverse forms such as painting, music, dance, architecture, and literature. Some definitions focus on their intrinsic aesthetic qualities, while others understand art as a socially constructed category. Art interpretation and criticism seek to identify the meanings of artworks. Discussions focus on elements such as what an artwork represents, which emotions it expresses, and what the author's underlying intent was.

Diverse fields investigate aesthetic phenomena, examining their roles in ethics, religion, and everyday life as well as the psychological processes involved in aesthetic experiences. Comparative aesthetics analyzes the similarities and differences between traditions such as Western, Indian, Chinese, Islamic, and African aesthetics. Aesthetic thought has its roots in antiquity but only emerged as a distinct field of inquiry in the 18th century when philosophers systematically engaged with its foundational concepts.

Aesthetics, sometimes spelled esthetics, is the systematic study of beauty, art, and taste. As a branch of philosophy, it examines which types of aesthetic phenomena there are, how people experience them, and how objects evoke them. This field also investigates the nature of aesthetic judgments, the meaning of artworks, and the problem of art criticism. Key questions in aesthetics include "What is art?", "Can aesthetic judgments be objective?", and "How is aesthetic value related to other values?". One characterization distinguishes between three main approaches to aesthetics: the study of aesthetic concepts and judgments, the study of aesthetic experiences and other mental responses, and the study of the nature and features of aesthetic objects. In a slightly different sense, the term aesthetics can also refer to particular theories of beauty or to beautiful appearances.

Aesthetics is closely related to the philosophy of art and the two terms are often used interchangeably since both involve the philosophical study of aesthetic phenomena. One difference is that the philosophy of art focuses on art, whereas the scope of aesthetics also includes other domains, such as beauty in nature and everyday life. This leads some theorists to argue that the philosophy of art is a subfield of aesthetics. However, the precise relation between the two fields is disputed and another characterization holds that the philosophy of art is the broader discipline. This view argues that aesthetics mainly addresses aesthetic properties, while the philosophy of art also investigates non-aesthetic features of artworks, belonging to fields such as metaphysics, epistemology, philosophy of language, and ethics.

Even though the philosophical study of aesthetic problems originated in antiquity, it was not until the 18th century that aesthetics emerged as a distinct branch of philosophy when philosophers engaged in systematic inquiry into its principles. The term "aesthetics" was coined by the German philosopher Alexander Baumgarten in 1735, initially defined as the study of sensibility or sensations of beautiful objects. The term comes from the ancient Greek words aisthetikos, meaning 'perceptible things', aisthesthai, meaning 'perceive, see', and aisthesis, meaning 'sensation, perception'. The earliest known use in the English language happened in a translation by W. Hooper in the 1770s.

The domain of the aesthetic encompasses a variety of properties, objects, experiences, and judgments associated with beauty and artistic expression. However, the exact boundaries of this domain are disputed—it is controversial whether there is a group of essential features shared by all aesthetic phenomena or whether they are more loosely related through family resemblances. Another central topic concerns the relation between different aesthetic concepts, for example, whether the concept "aesthetic object" is defined through the concept of "aesthetic experience".