Apache Pulsar is a distributed, open-source messaging and streaming platform designed for high-performance, scalability, and data consistency. It combines the features of traditional message queues with those of publish-subscribe systems, providing unified platform for real-time event streaming and messaging.
Apache RocketMQ is a distributed messaging and streaming platform with low latency, high performance and reliability, millions of TPS and storage capacity, and flexible scalability. It was originally developed by Alibaba and later open-sourced as an Apache project.
RabbitMQ is a widely-used open-source message broker software. It acts as an intermediary for messaging, providing a common platform for applications to send and receive messages. It is based on the Advanced Message Queuing Protocol (AMQP) and supports multiple messaging protocols.