Freewriting is nothing more than what it says, to write freely, without the inner critic or the grammer police intervening. You can start with or without a prompt (a picture, a word, a topic, a thought) or just set the clock for 10, 15 or 20 minutes and just write out your gut. Never stop writing, neither reread or cross out any lines, just keep on going. Anything you write is okay, as it's just for you. Finish your sentence as the alarm goes and set off for a second session if needed. Besides often working therapeutically, freewriting can push you to register strange but interesting thoughts and observations, that are worth picking up again.
Freewriting
Intent: Shutting down the inner critic through freewriting