This book investigates media's influences on the acculturation of North Korean refugee young adults in South Korea, especially focusing on identifying the role of online social media. The study analyzed the acculturation and media patterns of the refugee young adults and revealed that online social media and mass media served distinctive functions in the acculturation processes of the refugee young adults. Mass media allowed the refugees to learn a given culture from secondary experiences by providing cultural information in one-way communication. One the other hand, online social media provided a social channel to the refugees where they were able to learn and grow within the host and ethnic cultures from the real interactions with South Koreans and other refugees. These findings indicate that the acculturation process of North Korean refugee young adults is significantly influenced by the dynamic interactions between South Korean media and North Korea-related media and also between the mass media and online social media.