Ansible

Ansible is an open-source automation tool that focuses on configuration management, application deployment, and task automation. Unlike Terraform, which excels at provisioning infrastructure (the 'day one' tasks), Ansible excels at configuring what's inside that infrastructure (the 'day two' tasks). For example, you might use Terraform to create a fleet of virtual machines, and then use Ansible to install specific software, configure security settings, and deploy your application code onto those machines. One of Ansible's defining features is its 'agentless' architecture. It communicates with managed nodes over standard protocols like SSH (for Linux) or WinRM (for Windows), so you don't need to install any special client software on the servers you want to manage. Ansible works by executing 'playbooks', which are simple YAML files that describe the desired state of a system. A playbook is a list of 'plays', and each play maps a group of hosts to a set of 'tasks'. Each task calls an Ansible 'module', which is a reusable unit of code that performs a specific action, like installing a package, starting a service, or copying a file. This simple, human-readable YAML syntax makes it very easy to get started with automation.