Apache Hadoop is an open-source framework designed for storing and processing large datasets across clusters of computers. It allows for the distributed storage and analysis of data, making it easier to handle big data applications. The framework is built on a few key components, including the Hadoop Distributed File System (HDFS) for data storage and MapReduce for processing tasks. Hadoop is highly scalable, meaning it can grow with the needs of an organization by adding more machines to the cluster. It is widely used in various industries for tasks such as data analysis, machine learning, and data warehousing, enabling businesses to gain insights from their data efficiently.