When carrying out Continuous Delivery and deployment, there is no one size fits all deployment strategy. Configuration management tools such as Puppet, Chef, Ansible, and Salt have different approaches to deployment and use different approaches when keeping servers up to date.
The tool that is selected is not important, only the ideal workflow and processes to support delivering changes that are consistent, quick, and accurate.
Tools such as Puppet and Chef adopt a centralized approach to configuration management, where they have a centralized server that acts as the brain for the deployment process.
In Puppet's case the centralized server are the Puppet Master and in Chef's case the centralized server is the Chef ...