Need is a term used to describe something essential for human life, such as food, water and shelter. Needs are different from wants, which are desires or wishes for things that are not essential to survival. People may sometimes use the terms want and need interchangeably, but they have different meanings. The difference between needs and wants is important for many areas of life, including philosophy, psychology, biology, social science and economics.
Needs are the fundamental requirements that people need to meet in order to be happy and healthy. According to the psychologist Abraham Maslow, people have a hierarchy of needs ranging from basic physiological needs such as food, water and shelter through to psychological needs for belonging, esteem and self-actualization. If these basic needs are not met, it can lead to illness or even death.
Physiological needs are a group of the fundamental requirements that a person has for a healthy and productive life, such as air, food, water and shelter. These include basic physiological needs such as hydration, nutrition and sleep and also safety needs for avoiding injury or disease. Psychologist Abraham Maslow proposed that these basic needs are the most crucial for human happiness and survival.
The term need can also be used to refer to an individual’s desire for a specific outcome or goal, such as wanting to lose weight, learn a new skill, achieve a promotion or get married. Alternatively, the phrase need can be used to refer to an obligation or duty a person feels towards someone else, such as needing to help a friend in need or needing to be responsible for their actions.
When referring to health care, need can mean either the ability or inability of an individual to receive health care services, or a subjective judgment about appropriate treatment. At the societal level, it can also refer to what the government or private industry is willing to provide, taking into account factors such as resource constraints and cultural norms.
In English, the modal verb need is commonly used in present-tense questions and negations and in conditional clauses: Do you need any more evidence? – Yes, I do, but I haven’t found it yet. It can also be used in the pattern need not have/needn’t have plus a past participle: He needn’t have taken the exam.
In other languages, need has been used to express similar concepts, such as the grammatical requirement that an action be performed, and the logical concept of requisite behaviour. Need is a common feature in the vocabulary of many cultures, especially in those that have a strong oral tradition. In some languages, such as Japanese and Korean, the word is pronounced differently from the standard English pronunciation. In some cases, this is due to phonetics; in others, it is due to a lack of a distinct phonological feature for the word in the language. For example, the Korean word for need is neodi, while the Finnish word is neede.