Cloudinary is a cloud service that provides smart image manipulation and management. It acts as storage, backup, a content delivery network, and image transformer. Cloudinary is useful because image management is difficult without many options, and it provides flexibility and speeds up websites. Developers should integrate Cloudinary as early as possible to move all image assets to the cloud service. It has a simple URL structure and works with common frameworks like Carrierwave. Cloudinary offers private images, sprite generation, face detection, metadata support, and image optimizations for mobile. Developers get one account to use across multiple sites.