A Message Queue is a communication method used in software systems to allow different parts of an application to send and receive messages asynchronously. This means that one part of the system can send a message to the queue without waiting for the other part to process it, enabling better performance and scalability. When a message is placed in the queue, it is stored until the receiving component is ready to process it. This decouples the sender and receiver, allowing them to operate independently. Common implementations of message queues include systems like RabbitMQ and Apache Kafka.