Art
Art is a diverse range of human activities in creating visual, auditory or performing artifacts (artworks), expressing the author's imaginative or technical skill, intended to be appreciated for their beauty or emotional power. In their most general form these activities include the production of works of art, the criticism of art, the study of the history of art, and the aesthetic dissemination of art.
Design
Design is the creation of a plan or convention for the construction of an object, system or measurable human interaction (as in architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns). Design has different connotations in different fields (see design disciplines below). In some cases, the direct construction of an object (as in pottery, engineering, management, coding, and graphic design) is also considered to use design thinking.
Management
Management (or managing) is the administration of an organization, whether it is a business, a not-for-profit organization, or government body. Management includes the activities of setting the strategy of an organization and coordinating the efforts of its employees (or of volunteers) to accomplish its objectives through the application of available resources, such as financial, natural, technological, and human resources. The term "management" may also refer to those people who manage an organization.
Design
From a structural point of view, design is totally useless... I tried to give my products a little sense and energy. But even when I gave the best of myself, it was absurd.
Philippe Starck (2008) in: "Les doutes existentiels de Philippe Starck", Marie-Douce Albert, Le Figaro, March 28, 2008, p. 32
Management
Management as an activity has always existed to make people’s desires through organized effort. Management facilitates the efforts of people in organized groups and arises when people seek to cooperate to achieve goals.
Daniel A. Wren and Arthur G. Bedeian. The evolution of management thought, 1972, p. 11-12
Design
This is exactly the meaning of design: the conflict between form and content, form being the problem. [...] It is the coming together of form and content that is the realization of design.
Paul Rand (2008), Conversations with Students p. 32