A data lake is composed of numerous components that work together to store, process and analyze massive amounts of data. At its most basic, it includes the physical infrastructure such as servers and storage devices, as well as the software that enables data input and output. Additionally, there are two other key components to a data lake: metadata and security. Metadata provides an organized view into the structure of the data being stored and allows for efficient search within the data lake. Security sits on top of the data lake to ensure effective access control as required by internal policies or external regulations. With all of these components in place, a data lake can provide an invaluable resource to any organization looking to extract meaningful insights from big data.