Variables can be used to define variables that can be used in flows as conversational output. For example, when multiple flows that belong to different intents provide a link to a website in a flow, then the link can be added as a variable.
This is demonstrated below:
Message without variable: "Please visit https://www.blits.ai/ for more information"
Message with variable: "Please visit
[link] for more information"
Should this link become obsolete in the future, then it can easily be adjusted in the variables page. This way, the user does not need to go through every flow to find Dialog blocks that use this link and to change it accordingly.