The Microsoft Azure Luis Runtime Client is a software tool that enables developers to access and interact with the Language Understanding Intelligent Service (LUIS) in the Azure cloud platform. This client provides a seamless way for applications to leverage LUIS, a natural language processing service that helps understand user input and intents. With the Azure Luis Runtime Client, developers can easily integrate LUIS into their applications, allowing them to build intelligent and conversational interfaces that can accurately comprehend and respond to user queries and requests. The client streamlines the process of connecting to LUIS and provides the necessary functionality to process and interpret user input efficiently.