Social media usage has grown to become one of the most pervasive cultural phenomena in America. Not engaging in social media, for many businesses, can be a death sentence—especially now that it has become so ubiquitous in the business world.

Engaging, however, requires a keen grasp of the whys. Simply knowing how to write an eye-catching headline or posting a tweet to a thread on Twitter isn’t enough. To really get into the mindset necessary to succeed on social media, marketers and salespeople have to understand the reasons behind every step of the process.

Why do people share things on social media that they might not share face-to-face? Why do people care about others’ social media presence? In what ways do people manifest their own identities using social networks?

A study by the New York Times Consumer Insight Group identified five major reasons people choose to share what they do on social media sites. 49% of participants in this study said that they shared to inform other people about what they care about or to affect new opinions or encourage action in others. It’s reasonable to assume that at least one of these factors plays a role in nearly every tweet, re-blog, or post someone displays on their social media account. And while these impulses may be tempered by other desires or urges, they can be considered the core of sharing, from which many other components come.

For marketers, two of these reasons are very closely related (self-fulfillment and supporting a cause) and accordingly have been collapsed into a single description.

The most compelling reason to share, supporting a cause, affected the social media patterns of as many as 84% of survey respondents. These shares can come in large and small forms, ranging from a simple tweet in support of one side of a recent political issue to participation in a widespread, momentous event.

One organization that hit social media gold with a visible, effective supporting-a-cause campaign was The Amyotrophic Lateral Sclerosis (ALS) Association. Its Ice Bucket Challenge, in which individuals dumped buckets of ice-cold water on themselves and challenged others to either do the same or donate to the ALS Association, completely enveloped social media during its prominence. Politicians, business leaders, sports figures, and celebrities all got in on the act, dumping ice on themselves and raising awareness—and money—for a worthy cause. These videos saw tremendous play among fans of major public favors, fueling their virality.

While some people might be prone to sharing any video that their favorite celebrity endorses, the Ice Bucket Challenge drew on another major pillar of social sharing: self-fulfillment. The challenge allowed those sharing it to feel as though they were making a difference in addition to supporting something worth the effort. Shared videos put more eyes on the challenge, and viewers could choose to participate themselves without much effort. Sharers not only felt entertained—they felt empowered, too.

No discussion of social media would be complete without a least touching on the fact that it is called social for a reason. 78% of the NYT survey respondents indicated that they shared information to stay in contact with people who they otherwise might lose track of, or who would slip out of their lives.

To see this principle in action, one needs to look no further than Facebook. Individuals often add people to their friends lists who, under normal circumstances, they wouldn’t consider much more than casual acquaintances. People will often maintain Facebook friendships long after moving away from a region, staying in touch with those they can no longer simply see face-to-face in a casual setting. By sharing things that will potentially get these friends engaged, people can keep friends’ attention and feelings of friendship long after they stop seeing each other on a regular basis.

Although this doesn’t have as much direct application for marketers, it can serve as an important reminder that each customer’s reach is just a little bigger than markets might expect. These connections can, in turn, bring a message to an unexpected segment of the population. Every share matters, and the ones that matter most might not be the ones that look like they would on paper.

For 68% of respondents, sharing is about showing other people what they care about and who they are, whether it’s to their followers, their friends, or the world at large. Sharing content becomes a performative act—one in which the primary focus is self-description. “This is me,” the sharer says as they re-post a set of clips from Captain America. “This is me,” the sharer says as they retweet a comment from an infamous politician regarding the economy. For these social media consumers, the goal is first and foremost self-definition.

This core of sharing is particularly attractive for creative outlets like Instagram and Pinterest, as well as on platforms like Twitter and TikTok. People with the creativity to generate art and fiction often use social media this way, showing off the things they value through their work. Even easier, however, is offering one’s own thoughts on current issues or products through a tweet. Something as simple as “I like Starbucks” can fulfill that urge to say, “Hey—this is what I’m about.”

The least common motivator of the core set, entertainment and product passion motivates about 49% of shares according to the NYT study. People share information on the brands, products, and activities they enjoy either to get more friends to enjoy the same things, or to affirm a specific identity among friends who they already know care about the same things.

This motivator explains phenomena like the mirroring of videos on YouTube or the sharing of viral videos. People like to do simple, enjoyable things on social media, and there’s nothing more enjoyable than doing something one already knows is enjoyable and then sharing the experience. Users who are interested in a company’s products in the first place, before marketing or advertising campaigns, often share for this reason, and typically form the backbone of any viral campaign. Without this core of initial followers to get the engine started, most such campaigns will fizzle out before they ever get going.

While outrage on the Internet can keep people engaged in modest doses, negativity is exhausting; positivity on the other hand, positivity will always be uplifting and entertaining. People are often just looking to have a good time on social media, but the reason for the rapid spread of positivity through social networks has to do with the social presence one wants to promote, at least according to one researcher.

A social psychologist at the University of Pennsylvania, Dr. Jonah Berger, argues that bad news and shocking situations work for broadcast media, but social media works differently. He says that in social media, the reaction is what matters more than anything else. Those using social media don’t want their friends to see them as depressing, angry, or tedious, and accordingly, the things they tend to share are happier and lighter.

By looking at the share rates of various articles on the New York Times website and controlling for factors like page positioning and article size, Dr. Berger and his colleagues discovered that the most popular articles had a few traits in common. Often, the articles saw proportionally higher share rates when they inspired excitement, laughter, or awe in readers. Topics like science or feel-good stories about New York City earned significantly more attention than deaths or catastrophes.

Similarly, when people’s enthusiasm and excitement were measured using brain monitoring equipment, the number one predictor of enthusiasm was “what appeals to others.” The idea of getting other people enthusiastic is one of the major impulses behind sharing. There’s an element of validation-seeking to it as well. Studies have also found that people enjoy talking about themselves and like chances to make themselves seem positive in front of large audiences. This urge—to be seen by lots of people and to have that seeing feel positive—gets strong results when it comes to sharing.

As social media continues to grow, it becomes more and more apparent that why people participate in it changes just as much as how they do. At different stages in their lives people are looking for different things—and how they use social media is informed by those unique needs.

Senior citizens, for example, use social media differently. The significant time they have to use social media makes them greater social campaign targets than one’s gut might say, and social media holds something unique for these individuals: the chance to look back. Communicating with old friends is easier, and the common platforms provide great opportunities to look back on times well spent. Even if they don’t participate, they’re watching.

For those between 34 and 60, social media provides an opportunity to constructively interact with one’s environment and strengthen relationships. These people are often seeking ways to compartmentalize their social environments through social media. They may use one account solely for business activities, while another or even a different platform entirely fulfills family needs.

For marketers, this data suggests that even when social media is an essential part of a company’s strategy, one approach won’t fit every market. Different people are often looking for fundamentally different things out of the time they spend on social media, and serious consideration of the age group one’s targeting is necessary to get the most out of the time and money spent.