Need

A need is something that is necessary for an organism to live a healthy life. Needs are distinguished from wants in that, in the case of a need, a deficiency causes a clear adverse outcome: a dysfunction or death.

Needs can be objective and physical, such as the need for food, or subjective and psychological, such as the need for self-esteem.

There are also needs of a social or societal nature.

Needs and wants are a matter of interest in, and form a common substrate for, the fields of philosophy, biology, psychology, social science, and politics.

Psychological definition

To most psychologists, need is a psychological feature that arouses an organism to action toward a goal, giving purpose and direction to behavior.

The most widely known academic model of needs was proposed by psychologist Abraham Maslow. His theory proposed that people have a hierarchy of psychological needs, which range from security to self-actualization. However, while intuitively appealing, this model has been difficult to operationalize experimentally. It was developed further by Clayton Alderfer.

Design

Design is the creation of a plan or convention for the construction of an object or a system (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, cowboy coding and graphic design) is also considered to be design.

Designing often necessitates considering the aesthetic, functional, economic and sociopolitical dimensions of both the design object and design process. It may involve considerable research, thought, modeling, interactive adjustment, and re-design. Meanwhile, diverse kinds of objects may be designed, including clothing, graphical user interfaces, skyscrapers, corporate identities, business processes and even methods of designing.

Thus "design" may be a substantive referring to a categorical abstraction of a created thing or things (the design of something), or a verb for the process of creation, as is made clear by grammatical context.