The document discusses several use cases for using Node.js in production applications. It describes using Node.js to build APIs for an advertiser backend and ridesharing app due to their need to handle many small requests and lack of complex business logic. However, Node.js was not used for a hotel booking system because it involved significant business logic, which frameworks like Ruby on Rails addressed well through conventions. The document stresses evaluating libraries available for tasks, preparing to modify code as needed, and understanding the different challenges of Node.js in production environments.