Which review involves a less formal process, lacking documented procedures?

The correct answer is the informal review. This type of review is characterized by its unstructured nature and absence of formal procedures or documentation. Informal reviews are often conducted in a casual manner, where team members may discuss and provide feedback on a piece of work without following a predefined checklist or adhering to strict guidelines. This flexibility allows for quick feedback and collaboration, making it suitable for early stages of development or in scenarios where speed is crucial.

While other review types, such as technical reviews or quality reviews, usually involve defined processes, roles, and documentation to ensure thorough assessment and improvements, the informal review thrives on direct communication and spontaneous discussions. This makes it particularly effective for quick assessments or minor adjustments, thus fostering an open exchange of ideas without the barriers that formal processes can sometimes impose.