<![CDATA[English development in the digital age increasingly unfolds within the dynamic, multimodal spaces of social media rather than exclusively in formal classrooms. Yet, empirical evidence detailing how specific digital linguistic features influence adolescent learners in non-Western EFL contexts remains limited. Addressing this gap, this study investigates how Indonesian senior high school students adopt and integrate informal English expressions such as slang, acronyms, abbreviations, and hashtags from social media into their communicative practices. Using a mixed-methods descriptive design, data were collected from 66 students through a structured questionnaire, open-ended items, and semi-structured interviews. The findings reveal four key patterns: (1) frequent and habitual use of English across digital platforms; (2) significantly increased confidence supported by low-pressure, asynchronous interaction; (3) systematic and purposeful adoption of informal linguistic features for expressiveness and social alignment; and (4) cross-contextual migration of digital expressions into offline communication accompanied by register awareness. These results indicate that social media operates as a parallel linguistic ecosystem that fosters communicative agency, pragmatic flexibility, and identity construction rather than linguistic deterioration. The study’s originality lies in its empirical focus on concrete digital linguistic forms within a secondary school EFL context in Indonesia, a setting underrepresented in prior scholarship. By reframing informal digital language as an adaptive communicative resource, this research contributes to discussions on informal digital learning of English and offers pedagogical implications for integrating students’ digital repertoires into context-sensitive English language teaching in the broader global EFL landscape.]]>
