Ansible is a configuration management tool that uses an agent-less architecture to manage changes across infrastructure components. Handlers in Ansible are special tasks that help manage conditional execution of specific tasks, ensuring that configuration changes only trigger necessary actions. They are essential for adding flexibility and responsiveness to Ansible playbooks. Handlers are executed towards the end of a playbook if notified by other tasks and can be triggered using the notify or listen attribute. Using handlers helps avoid unnecessary restarts and ensures efficient execution of special operations in Ansible playbooks.