Sub-flows
Some flow blocks can be used to create sub-flows. These blocks act as a boundary between the main flow and the sub-flow and are highlighted in pink in the flow editor.
Contextual placeholders like the interaction
placeholders of the main flow aren't available in the sub-flow and are replaced with the interaction
placeholder of the sub-flow. Node results on the other hand remain available.
Modals
Modals are a special type of sub-flow. They are used to create interactive experiences. When a modal is opened, the flow execution is suspended and the modal is displayed to the user. The flow execution is resumed when the modal is submitted. You can then access the results of the modal in the main flow using the interaction.components
placeholder.
Modals can be used to create interactive experiences like forms, quizzes, etc.