Ansible is an automation tool for the configuration, provisioning, and management of cloud and on-prem resources. It makes a difference in the way of deployment as it is an SSH-based tool and comes with a very easy and secure connection. It is very easy to get started with Ansible for people coming from a Linux background.
Ansible is an agentless tool, you need to install it in on one controller machine and whenever you want to make a deployment, run it from your controller machine, provide the host list, and deploy it in all the nodes. All commands are run through Ansible via SSH, and if Ansible needs updating, you only need to update your single control machine.
You can also check the version and software status, for example, if you want to check whether Apache is installed on all the machines or not, Ansible will give you a machine list where Apache is not...