- LWRP and HWRP allow creation of custom resources in Chef. LWRP are lightweight while HWRP are heavyweight. - Data bags store JSON data on the Chef server that can be accessed from recipes. Data bag items contain individual JSON files that can be encrypted. - Linting tools like Rubocop and Foodcritic ensure code quality by analyzing code for conventions and best practices. - Berkshelf manages cookbook dependencies externally to the Chef server. Test Kitchen tests cookbooks across platforms in isolation using drivers. - Chef-solo runs locally without a server while Chef-zero is an in-memory server for development. Chef-provisioning declaratively defines machine resources across