Freewriting is a method used by writers where you timebox your writing and write whatever comes to mind. It can be useful to get your writing session started, for journaling at the start of the day to gain clarity or to get through a Writer’s Block.
The outcome of a freewriting session is often unimportant and can be stored or discarded. It’s the process itself that helps clear mind and warm up the thinking and writing muscles.
750 Words is a popular service if you want to use one but a pen and paper or a blank note on your digital system works just as fine.