From the growth of TikTok and of social commerce to the challenges of brand safety and the cookieless future, 2021 will be another year of big stories for social media.

After a tumultuous year, the social platforms will close 2020 on a high note in terms of ad revenues and users—and with features that closely resemble each other.

The pandemic has brought an influx of new users for subscription OTT, live videos, and video games in 2020, but other activities such as social networking, mobile messaging, and digital video haven’t seen the same bump.

YouTube has been the OG for video creators for years, but now the social properties are making bigger inroads into this popular content format. That’s bringing new ways for marketers to work with creators on Facebook, Snapchat, TikTok and more.