Filterworld: How Algorithms Flattened Culture explores how the evolution of recommendation technology has taken these back-end processes and turned them into powerful curatorial mechanisms for culture. Kyle Chayka's work suggests that by way of recommendation-based social media (Instagram), video (TikTok), music (Spotify) streaming and movie/TV viewing (Netflix), and many others like them, these services do more than just tailor an individual's experience through personalization; they help decide which cultures are created, consumed, and seen. The reviewers feel the book's best contribution is demonstrating the relationship between recommendation via algorithm and less culturally diverse output while at the same time acknowledging one major limitation in their analysis of causal relationship. There is substantial research on recommender systems showing that there is indeed reason to worry about reduced cultural variety; however, the body of evidence regarding the impact of decreased diversity does vary widely depending on both platform and user. Therefore, Filterworld should be viewed as most beneficial as a model or framework for examining who determines what becomes discoverable and ultimately what types of culture become invisible.