Hi JayPea,
You are referring to an image, but probably you forget to add it to your post?
The client variable allows you to save something on the browser which is quite useful to avoid the need to go to the server (better performance and can be accessed offline), although it should be used with care and avoid storing sensitive information there.
To hold the values a user used a filter is a perfect and one of the most common examples on using client variables.
In this case, you would use it just like you would with a local variable, but unlike the local variable that gets its value reset when you navigate to another screen, the client variable holds the value until the session is reset (e.g. when the user logs out or logs in).
Kind Regards,
João