This chapter describes the ways in which emoji and language synchronise to realise textual meaning in a social media post. It organises these as features of a system network that describes this sychronicity. A primary distinction is made between instances where emoji replace linguistic co-text (inset) and instances where emoji accompany the linguistic co-text (punctuate) in a manner similar to punctuation or discourse markers. In terms of language, the key discourse semantic systems involved are identification and periodicity, which are crucial in tracking participants and organising information flow in texts. In terms of the SFL model of textual meaning, emoji appear to occupy a wavelength between clauses and higher-level periodicity, while the unique affordances of emoji also provide new opportunities for creating meaning in texts.