What kinds of jobs is Ansible used for?

It combines software distribution, ad-hoc command execution and software configuration management, for example to build infrastructure, deploy software, install updates and template common tasks.

Typical uses:

1. Building and managing infrastructure and virtual machines.
2. Deploying software and configurations.
3. Installing software updates across many machines.
4. Distributing local VMs, for example identical lab machines.
5. Remote management of the cloud and deployment into it.
6. Templates for common tasks, written once and reused.

The three underlying capabilities are:

• software distribution: getting packages and files onto machines;
• ad-hoc commands: running a one-off command on many hosts at once, such as ansible all -m ping;
• configuration management: keeping machines in a defined state over time.

Go deeper:

• Introduction to ad hoc commands (official docs) — one-off reboots, file copies, package and user management across many hosts.
• Ansible 101 - Episode 2 - Ad-hoc tasks and Inventory (Jeff Geerling) — live demo of ad-hoc commands against a group of servers.