The business events catalog lists the business events that are available in your Finance and Operations application. The business events catalog can be accessed from System administration | Set up | Business events. 

The following screenshot shows the user interface of the business events catalog in Dynamics 365 for Finance and Operations:

The business events list is built during the code deployment process of the Finance and Operation environment. However, if an explicit update of the catalog is required, this can be done using the MANAGE | Rebuild business events catalog option. 

Each business event that's available in the catalog contains a category, business event ID, and description. It also contains the payload that will be generated when business events occur. You can also download the payload schema in JSON format.

In summary, the business events catalog helps identify the business events that are required for implementation purposes. It also helps identify the schema for each business event.