The document discusses the concept of big data, characterized by large and complex data sets that challenge traditional data processing methods, highlighting its growing volume from various sources like social media and stock exchanges. It outlines key attributes of big data, known as the 4 V's: volume, velocity, variety, and veracity, and elaborates on types of data including structured, semi-structured, and unstructured. Additionally, it introduces Hadoop as an open-source framework for processing large data sets in a distributed environment, detailing its core components, HDFS and MapReduce.