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id: version-2.6.0-concepts-overview title: Pulsar Overview sidebar_label: Overview original_id: concepts-overview

Pulsar is a multi-tenant, high-performance solution for server-to-server messaging. Pulsar was originally developed by Yahoo, it is under the stewardship of the Apache Software Foundation.

Key features of Pulsar are listed below:

• Native support for multiple clusters in a Pulsar instance, with seamless geo-replication of messages across clusters.
• Very low publish and end-to-end latency.
• Seamless scalability to over a million topics.
• A simple client API with bindings for Java, Go, Python and C++.
• Multiple subscription types (exclusive, shared, and failover) for topics.
• Guaranteed message delivery with persistent message storage provided by Apache BookKeeper.
• A serverless light-weight computing framework Pulsar Functions offers the capability for stream-native data processing.
• A serverless connector framework Pulsar IO, which is built on Pulsar Functions, makes it easier to move data in and out of Apache Pulsar.
• Tiered Storage offloads data from hot/warm storage to cold/longterm storage (such as S3 and GCS) when the data is aging out.

Contents

• Messaging Concepts
• Architecture Overview
• Pulsar Clients
• Geo Replication
• Multi Tenancy
• Authentication and Authorization
• Topic Compaction
• Tiered Storage