Critique is an examination of a story’s components and how they work together, in order to identify strengths and weaknesses. The goal is to help the author tell her story in the best way she can. Copy editing, identifying grammatical and structural language problems, isn’t the same as a critique, though critique may include copy editing. Whether you’re new to it or you’re trying to change your process, critique can seem a lot more daunting than it really is.
Most artists don’t improve and grow without some external input; it’s often tough to identify weaknesses in your own work. Critiques are one of the best ways for artists to improve, because they provide the response of an audience, showing you what didn’t successfully transfer from your internal context to the rest of the world.