[Write a perfect introduction pages including all of the information below. Make sure to rewrite to your own words smoothly.] –Social network such as Facebook or Instagram made a whole new world on online, it is a new communication channel. -(Write pros and cons of smartphone and social network such as Instagram) -“Selfie” is a one of the new way to introduce yourself and to communicate with other people. -because of the “Selfie”, Instagram could grow up so fast. –Social network: a network of social interactions and personal relationships (oxford dictionary) -Indeed, age is a strong determinant of the frequency and quality of an individual\’s social media usage, and it is unsurprising that younger people are more comfortable with online communication than adults (Thayer & Ray, 2006). -Ostensibly, the heightened interpersonal connectivity afforded by social media should be associated with an overall increase in psychological well-being, yet the problem of loneliness persists in the same societies where social media usage is likely at its highest (e.g., the US, the UK, etc.). -notable phenomenon that has received considerable attention over the years is that individuals utilize SNSs as a means for self expression and self-presentation (e.g., Mehdizadeh, 2010; Zhao,Grasmuck, & Martin, 2008). -Through a mixture of content they post and share on SNSs, such as profile status updates, photos, videos, or comments, individuals can strategically construct and maintain their self-identities. Indeed, with the intention of impression management, individuals are found to display their positive and socially desirable self on SNSs (Buffardi & Campbell, 2008; Kr€amer & Winter 2008; Zhao et al., 2008). With the recent proliferation of photo-sharing SNS platforms, such as Instagramor Pinterest, photo-posting and sharing activities on SNSs have gained immense popularity, making them a unique and fast-emerging phenomenon in digital environments. -Besides their skyrocketing incidence, selfies have received mounting attention from researchers and practitioners in psychology and communication as they represent image-based self presentation on SNSs (e.g., Chua & Chang, 2016; Qiu, Lu, Yang, Qu, & Zhu, 2015). There has been a constant growing interest with regard to individuals\’ needs and dispositions underlying online presentation on SNSs. Studies have examined various personality factors associated with self-presentation on SNSs including photo-posting, -Given that selfie-posting is associated with self-promotion through a selective collection of photographs of oneself (Mehdizadeh, 2010), selfies are regarded as an explicit form of self-portraits on SNSs projecting positive and desirable self-images. With this inherent nature, selfie-posting on SNSs has been found to be associated with narcissism by recent studies (e.g., Fox & Rooney, 2015; Sorokowski, Sorokowska, Oleszkiewicz, Frankowiak, & Pisanski, 2015; Weiser, 2015). -In order to calculate Narcissism, we used Emmons(1887)’s 37 questions NPI(narcissistic personality inventory). -Drawing upon the Theory of Planned Behavior (TPB; Ajzen, 1985, 1991) framework, the present study not only tests the applicability of the TPB in selfie-posting behavior on SNSs, but it also extends the framework by incorporating a personality variable, narcissism. Specifically, this study identifies and empirically examines four key predictors of selfie-posting on SNSs attitude toward behavior, subjective norm, perceived behavioral control, and narcissism. -Many researchers have examined individual differences in social mediausage. The results of these studies suggest that social media activity is related to characteristics of the Five Factor Model (Ross et al., 2009; Ryan & Xenos, 2011) and jealousy (Muise, Christofides, & Desmarais, 2009). Narcissism has also been shown to predict online social activity. Researchers have found that individuals characterized by relatively elevated narcissism are egocentric, have a sense of grandiosity, dominance, and entitlement, and perceive themselves as more attractive and better than others, but –importantly – are still marked by insecurity (Fox & Rooney, 2015;Raskin & Terry, 1988). Researchers studying narcissism have generally suggested a positive association between this characteristic and social media usage (Buffardi & Campbell, 2008; Carpenter, 2012; Lee, Ahn, & Kim, 2014; McKinney, Kelly, & Duran, 2012; Mehdizadeh, 2010; Ryan & Xenos, 2011).