Friendship is a term used to denote co-operative and supportive behaviour between two or more social entities. This article focuses on the notion specific to interpersonal relationships. In this sense, the term connotes a relationship which involves mutual knowledge, esteem, and affection. Friends will welcome each other's company and exhibit loyalty towards each other, often to the point of altruism. Their tastes will usually be similar and may converge, and they will share enjoyable activities. They will also engage in mutually helping behavior, such as exchange of advice and the sharing of hardship. A friend is someone who may often demonstrate reciprocating and reflective behaviors. Yet for many, friendship is nothing more than the trust that someone or something will not harm them.

Value that is found in friendships is often the result of a friend demonstrating on a consistent basis:

• the tendency to desire what is best for each other.
• sympathy and empathy.
• honesty, perhaps in situations where it may be difficult for others to speak the truth.
• mutual understanding.

In a comparison of personal relationships, friendship is considered to be closer than acquaintanceship, although there is a range of degrees of intimacy in both friendships and acquaintances. For many people, friendship and acquaintanceship lie along the same continuum.