Storing copies of data in multiple geographic locations to protect against regional disasters. Like keeping important documents in safe deposit boxes in different cities.
Cloud storage services keep your files in data centers across different continents so earthquakes or power outages can't destroy your data.
All provide durable object storage with copies in separate geographic locations. AWS uses cross-region replication between buckets, Azure offers built-in geo-replication options (GRS/RA-GRS), GCP uses dual-region placement within a chosen pair of regions, and OCI replicates objects between regions. They differ mainly in how you configure replication (policy vs. storage option), read access to the secondary copy, and replication scope/latency.