Wondering if anyone journals and finds it helps with their mental health?

Or if anyone uses a special diary with prompts? like…
“Something good that happened to me today was?”
“I’m excited for…”
“What did you love about today?”
“What were you challenges this week?” Etc.

If you use it, when and how does it help you?
If you wouldn’t try it, why not? 
If you’ve used one before, why did you stop?
Curious as to whether getting your thought  on paper helps! Is this a thing of am I wasting my time??