Cloud Storage is Google's object storage service. Upload files (images, videos, backups, datasets) to a bucket. Highly durable (99.999999999%), available globally, and cheap ($0.02/GB/mo). Built on the same infrastructure Google uses for YouTube, Gmail. You interact with buckets and objects (files). Unlike databases, Cloud Storage doesn't have structure (it's not relational). Perfect for unstructured data: media, logs, backups, data lakes.