Amazon Managed Streaming for Apache Kafka or Amazon MSK allows you to run applications that utilize Apache Kafka within AWS. Kafka provides a platform for stream processing and operates as a publisher/subscriber based durable messaging system. Its key features are the ability to intake data with extreme fault tolerance, allowing for continuous streams of these records that preserve the integrity of the data, including the order in which it was received.

Apache Kafka then acts as a buffer between these data producing entities and the customers that are subscribed to it. Subscribers receive information from Kafka topics on a first in, first out basis or FIFO, allowing the subscriber to have a correct timeline of the data that was produced.

Kafka is an open-source technology that allows for a large number of community-driven tools and add-ons. This makes it very customizable and gives developers the freedom to build and create what they need. Using Amazon MSK, you can use the native Apache Kafka APIs to create datalakes, stream information to multiple sources, and power data analytic applications and pipelines, again all within AWS.

The main reason you'd wanna use Amazon MSK over rolling your own implementation of Kafka is that Amazon MSK is a fully managed service. This means you don't need to take care of any servers, you don't need to worry about any upgrades and you also don't need to bother with handling Apache Zookeeper, a required coordinating software that deals with orchestrating the cluster task and maintaining the state of the cluster in general.