SQS S imple Q ueue S ervice First queue aws service from 2006 You create the queue and publish JSON messages into it Messages sit in the queue and can be processed at a later time Applications which want to retrieve messages have to poll the queue With SQS if you have 3 message subscribers only one first will be notified, others won't get the message This problem can be fixed by using 3 separate queues, but it leads to another problems and have scalability issues Usually SQS is used for one-to-one system, one system publish messages, one system process them SNS S imple N otification S ervice Also an old service from AWS Messages are published to a topic and this topic delivers identical message to a different subscribers of that topic Messages are also JSON messages There are publishers and subscribers (aka PubSub) of messages Contrary to SQS, in SNS we publish messages to a topic and can have multiple subscribers to that topic Message is deleted after it is delivered to all subscribers SNS usually do not interact with subscribers directly, because a subscriber may have a problem and message will be undelivered and have to stay in SNS Instead SNS sends messages to a dedicated SQS queue owned by subscribers EventBridge The newest guy from AWS Similar to SNS with some improvements Messages are published into the message bus and have different recipients, kind of topic in SNS. Events , like 'pending', 'shipped', 'delivered'. Can be constructed by application or AWS services itself or other 3rd services, like shopify. Rules match incoming events and sends them to corresponding targets for processing Targets are destination end-points, like subscribers. Message filtering is available Specific rule may have 5 targets, which is very low and may not fit your needs But it is very convenient due to AWS and 3rd applications integrations