Human beings are social animals. Most of us usually have numerous friends because we need friends not only to have an enjoyable life but also to grow as individuals. Our friends share our sorrows and joys and they help us better understand ourselves. Not all friendships are created equal because we form friendships with others for a variety of reasons. It may be appropriate to classify our friends into three groups, i.e. acquaintances, social friends, and best friends.
Acquaintances are friends we just happen to know in life. They may be our school fellows, our work colleagues, our neighbors, or just someone we met in a social setting. Our interactions with acquaintances are often formal and short. We may know basic details about them but we tend to avoid learning about their more personal matters. It could be argued that the acquaintances are the weakest form of friendship, and we make very little, if any, emotional investment in this form of friendship. The circle of acquaintances is usually the biggest among all types of friends because we simply tend to know lot more people than those we interact with on a regular basis such as social friends and best friends.

The second type of friends is social friends. The social friends could be defined as people whose company we enjoy. We may spend lot of time with them and we may know more about them than we know about acquaintances, but we usually avoid discussions about more personal issues unless given a signal or permission. Social friends have the potential to become one of our best friends over time but such friendships are not initially built on deep trust as much as they are built on common interests or shared social lifestyles. Our relationship with social friends is usually of higher quality than our relationship with acquaintances.

The third type of friendship is best friends. Our relationship with best friends is the deepest among all types of friends. We may share our deepest concerns and secrets with best friends that we may not share with social friends or acquaintances. Our best friends also have the most influence over us among all types of friends because we trust them. The circle of best friends tends to be the smallest among all types of friends because there are only so many people we can trust on a deep personal level. It is not uncommon for us to invest years in best friendships because longer time periods enable us to know people better.

We are social animals which may explain the presence of friends in our lives. The friends can be divided into three main categories which are acquaintances, social friends, and best friends. Acquaintances are people we happen to know, social friends are people whose company we enjoy, and best friends are people who have earned our trust. The circle of acquaintances tends to be the biggest for many people while the circle of best friends tends to be the smallest.