About action assets
The Input System stores your configuration of Input Actions and their associated bindings, action maps and Control Schemes in an action asset file. These Assets have the .inputactions file extension and are stored in a plain JSON format.
Project-wide action assets
The Input System creates an action asset when you set up the default project-wide actions, which is the most common and recommended workflow, but you can also create new empty action assets directly in the Project window.
Action maps
Actions assets allow you to group sets of related actions into action maps. For example, in an open-world city game, you might create separate action maps for different situations such as exploring on foot, driving a car, flying an aircraft, or navigating UI interfaces. This means, for most common scenarios, you don't need to use more than one Input action asset.