Lambda and Kappa are two data warehouse architectures that focus on how to handle streaming or real-time data, which is becoming more and more prevalent and important in data engineering. Streaming data is data that is continuously generated and consumed, such as web logs, social media, or IoT devices. Lambda architecture is based on the idea of having two layers or paths for processing streaming data: a batch layer and a speed layer. The batch layer is responsible for ingesting, storing, and processing data in batches, using traditional data warehouse tools and methods, such as ETL, SQL, or OLAP. The speed layer is responsible for ingesting, storing, and processing data in real-time, using streaming data tools and methods, such as Kafka, Spark Streaming, or Storm. The batch layer and the speed layer are then combined or reconciled to provide a consistent and accurate view of the data. Kappa architecture is based on the idea of having only one layer or path for processing streaming data: a stream layer. The stream layer is responsible for ingesting, storing, and processing data in real-time, using the same tools and methods as the speed layer in the Lambda architecture. The stream layer can also perform batch processing by replaying or reprocessing the data from the beginning or from a certain point in time. Kappa architecture simplifies the data pipeline and eliminates the need for maintaining and synchronizing two layers, but it also requires more robust and reliable streaming data tools and methods.