While defining the settings of a node, you can use data (event parameters) received in the preceding nodes in a diagram. This enables inserting dynamic values (for example, a customer's name or ID) in the input of the following nodes in a workflow or a request in a webhook. Such reuse in workflows is called the event context.
The complete documentation, instructions, and examples are available in "Event parameters" section in Automation inserts.
TIP: If you're not familiar with the Automation-related terms, check them in the dictionary.