Final answer:
A reference group is a social group that individuals use as a standard for their own behavior when making evaluations or decisions. It influences a person's social and personal development by providing norms and values for comparison.
Step-by-step explanation:
The concept that refers to a social group used as a point of reference when making evaluations or decisions is known as a reference group. A reference group is a group whose values, norms, and beliefs become a standard for an individual's behavior. In sociology, there are different types of groups one can belong to, including primary groups, secondary groups, in-groups, and out-groups. While primary groups are small, informal groups of people who are closest to us, such as family or close friends, secondary groups are larger and more impersonal. They are typically task-focused and time-limited, for instance, coworkers in a large company. Within these groups, people identify with certain groups and compare themselves to others, which are known as the in-group (or the group an individual is a part of and feels an affinity towards) and the out-group (or the group an individual is not part of and may feel competition or disdain towards).