Cloud Object Storage: S3, Blob Storage, and GCS Explained
Object storage is how cloud platforms store unstructured data: images, videos, documents, backups, static website assets, and any other files. Unlike a traditional filesystem, object storage is accessed via HTTP APIs — making it inherently accessible from anywhere and massively scalable.
The Major Object Storage Services
- Amazon S3 (Simple Storage Service): The original and most widely used cloud object storage. Industry standard with extensive ecosystem support.
- Azure Blob Storage: Microsoft's object storage — excellent integration with Azure services and Microsoft ecosystem
- Google Cloud Storage (GCS): Google's object storage — strong performance and BigQuery integration
- Cloudflare R2: S3-compatible storage with no egress costs — increasingly popular for cost-sensitive workloads
How We Use Object Storage
- Static assets: Application JavaScript, CSS, images, and fonts served via CDN with S3 as origin
- User-uploaded files: Files uploaded by your users stored in S3 — accessed via pre-signed URLs with time-limited access
- Backups: Database dumps and application data backups
- Data lake: Raw data files (CSV, Parquet, JSON) for analytics processing
- Application exports: Generated reports, exports, and downloadable files
Access Control
S3 buckets must be configured carefully — public access should be disabled by default. Access is granted through IAM policies (service access), pre-signed URLs (temporary user access), or bucket policies. We audit S3 bucket access configurations as part of security reviews — misconfigured public S3 buckets are a common source of data breaches.