Big data refers to large, complex datasets that come in a variety of formats from multiple sources. It is characterized by high volume, velocity, and variety of data, as well as additional Vs like veracity, value, and variability. Managing big data presents numerous challenges around storage, processing speed and volume, data integration and quality, extracting useful insights, privacy and security, scalability, and costs. Skills and tools are required to govern, manage, and analyze big data effectively.