A messaging service that allows applications to communicate asynchronously by sending messages through queues.
An e-commerce site uses Queue Service to process orders in the background without making customers wait.
All provide asynchronous messaging to decouple services. AWS SQS and Azure Queue Storage are queue-focused services; Azure Service Bus adds enterprise features (sessions, transactions, dead-lettering). GCP Pub/Sub is primarily pub/sub but can be used for queue-like work distribution via subscriptions. OCI Queue provides managed queues for decoupling and background processing.