Some people are born flirts — they just can't help themselves.

If they're waiting to get coffee, they'll flirt with the person standing behind them, the barista, and even the delivery guy.

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It's just the flirter's natural way of dealing with the world. If they like people and want nothing in return, then they might be more of a charmer than a flirter.

Some flirters have motivations that aren't simply to be friendly and kind; their motives are for gain, and to convince someone into giving them what they want. They're master manipulators.

In his 2004 review of literature on flirting, Northern Illinois University Professor, David Dryden Henningsen, identified six different kinds of motivation for flirting.

What are the 6 main reasons people flirt?

1. Sex

Flirting to get someone to sleep with you

2. Fun

Flirting as a sport

3. Exploring

Flirting as a relationship practice

4. Relational

Flirting to increase intimacy

5. Esteem

Flirting to increase one's own self-worth

6. Instrumental

Flirting to get something from another person  

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There's a huge difference between being charming and flirting.

If you have charm, you're trying to make everyone feel important.

If you flirt, you're using your sexual attractiveness to manipulate another person, sometimes in innocuous ways and other times in kind of creepy ways.

Both charmers and flirters make eye contact and have warmth in their voices, but flirters almost always have an agenda, such as getting their accounting instructor to change their grade or flirting their way out of getting a ticket.

Flirting can actually hurt people, especially when you take a flirter's actions or words seriously when that wasn't the true intention.

For instance, if a flirter is only flirting to see if they can get someone to respond and if that person believes the flirter's emotions are real, they might start thinking that it could lead to a relationship.

Obviously, they'll eventually be let down once the flirter achieves their goal and it will hurt.

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You will feel emotionally betrayed and that is never a good feeling, especially when it will probably sour your future relationships.

Some flirters are womanizers and narcissists who enjoy chasing a woman and then dumping her once they've got her.

Yes, these people exist and they find pleasure in making other people miserable.

You never know who might be flirting with you or if their intentions are real. That's why you should always keep your guard up at first until you figure out what type of person they are.

If they are a womanizer and/or a narcissist, then it won't take long for them to slip and reveal who they truly are.

Though flirting can be fun and harmless, it can also be manipulative and devious. Staying aware of different motivations behind flirting is a good way to protect yourself from being used.

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Christine Schoenwald is a writer and performer. She's had articles in The Los Angeles Times, Salon, Bustle, Medium, and Woman's Day.