Attraction is the first step to a meaningful relationship
Psychologists, sociologists, and anthropologists have long sought to determine the factors that cause a person to become attracted to another person. Humans are social beings. People form groups for common interaction, and lovers associate for romantic relationships and procreation.
In the past, people gathered in groups to live and hunt, activities that ensured the survival of the species in the short term. People procreate to ensure the long-term survival of the species.
Evolutionary psychology theorizes that the primary male attributes were strength and hunting prowess. Women instinctively selected mates who demonstrated these traits to ensure their survival and that of their offspring. The female’s reproductive capacity is limited by age and the long gestation period in humans. Conversely, the male’s ability to procreate is limited to the number of females that will allow him to copulate.
Because of these evolutionary limitations, women are generally attracted to men who display strength and prowess, traits that signal security. On the other hand, men are attracted to physical beauty, a sign of reproductive health. Today, physical security is not measured by a man’s ability to be a good hunter, but rather by his social status and ability to earn money and provide a safe environment for a woman and to his children.
The following selected principles are reliable predictors of attraction. Of course, as with all predictors of human behavior, there are exceptions to the rule.
Personality and attraction
Extroverts, compared to introverts, tend to appear more attractive because they are seen as gregarious and confident. Before entering into any type of relationship, knowing if the person you want to meet tends towards extroversion or introversion can provide valuable information.
If you’re an extrovert and the person you want to meet is an introvert, expect to see inherent differences in the way you view the world. Extroverts get energy from being with other people and seek stimulation from their surroundings. Extroverts often speak spontaneously, without thinking, and confidently use trial and error. Conversely, introverts expend energy when they engage socially and seek alone time to recharge their batteries. Introverts seek stimulation from within and rarely speak without thinking. Introverts weigh options carefully before making decisions.
Extroverts have a wide variety of relationships; however, these relationships tend to be superficial. On the other hand, introverts have few relationships, but those relationships tend to run deep. Introverts who date extroverts seek closer relationships, which extroverts may be less willing to commit to. This inability to easily make a deeper commitment highlights dissimilarity, which reduces mutual attraction.
People rarely exhibit fully extroverted or fully introverted characteristics. Personality traits slide along a continuum. Many people exhibit both extroverted and introverted characteristics. Additionally, introverts who are comfortable with their surroundings often display behaviors associated with extraversion. Likewise, extroverts may display introverted characteristics.
Self-esteem and attraction
People like to associate with people who display a high level of self-confidence. People with a high level of self-confidence tend to be comfortable being the center of attention. They may also be comfortable with self-disclosure, which is a building block in building close personal relationships.
Conversely, people with low self-esteem tend to be reluctant to disclose personal information. The inability to disclose is a defense mechanism to guard against criticism and rejection. Self-disclosure is the path to closer personal relationships, a path that people with low self-esteem are often unwilling to take. The fear of being abused, betrayed and rejected prevents people with low self-esteem from achieving what they most desire, a close personal relationship.
Use and attraction of Facebook
Similarity plays a vital role in developing relationships on Facebook.  Research reveals that Facebook users gravitate towards other Facebook users who share the same attitudes and beliefs. Facebook users are considered increasingly attractive as they approach 300 friends; however, when the number of friends exceeds 300, the effect on social attractiveness tends to diminish. 
People who spend too much time on Facebook are often seen as more introverted and have low self-esteem.  Introverts disclose more information on social media than when meeting face-to-face. The Facebook format allows enough time for introverts to formulate meaningful responses. Without the pressure of a face-to-face encounter, introverts naturally divulge more information than they would in personal conversations.
Introverts may also find it difficult to strike up conversations, especially with strangers. Social networks eliminate this additional social pressure. People with low self-esteem may also see Facebook as a supportive environment because they want to be accepted and liked by others. Social networks allow them to express themselves without being so directly exposed to negative comments.
Based on the limited research on relationship building on social media, it appears that the same psychological principles of attraction that are effective in face-to-face relationships apply to online relationships. In fact, social media offers an effective alternative method of communication for people who are not comfortable initiating face-to-face relationships.