Social media platforms are characterized by diverse features and functions, and these facets remain in constant flux over time. This research examines how users define the central qualities of four major platforms in the United States (Facebook, Twitter, Instagram, Snapchat), and how such lay definitions relate to key outcomes previously associated with social media use. In Study 1, we validated self-report measures using a comparative scaling approach to capture what users view as the most defining categories of the four platforms. In Study 2, we investigated whether lay definitions of platforms relate to perceptions of social affordances and social resources. Overall, results provided evidence that defining platforms as social interaction (vs. other qualities) is associated with amplified social affordances and resources. Together, the studies contribute to our understanding of how users navigate a dynamic online ecosystem, as well as how lay definitions may anchor the experiences and effects of social media.

社交媒体平台的特点是功能多样，这些方面随着时间的流逝而不断变化。这项研究调查了用户如何定义美国四个主要平台（Facebook，Twitter，Instagram，Snapchat）的核心素质，以及这种外行定义如何与先前与社交媒体使用相关的关键结果相关联。在研究1中，我们使用比较缩放方法验证了自我报告措施，以捕获用户认为是四个平台中最具定义性的类别。在研究2中，我们调查了平台的外行定义是否与对社会能力和社会资源的看法有关。总体而言，结果提供了证据，将平台定义为社交互动（相对于其他素质）与扩大的社会能力和资源相关。一起，