Amazon Glacier is specifically designed for data archiving and long-term backup where data is infrequently accessed. It offers extremely low-cost storage compared to other AWS storage services:

• Amazon Storage Gateway: Hybrid storage service that connects on-premises environments to AWS cloud storage
• Amazon EBS: Block storage service for EC2 instances, designed for frequently accessed data
• Amazon S3: Object storage for frequently accessed data (though S3 has different storage classes)

Amazon Glacier provides the most cost-effective solution for infrequently accessed data due to its archival pricing model and retrieval characteristics optimized for long-term storage.