Big data refers to large and complex datasets that are difficult to process using traditional database management tools. It is characterized by high volume, velocity, and variety of both structured and unstructured data. The volume of data being created is growing exponentially - from 2003 until now, the amount of data created each day has increased from 5 billion gigabytes to the same amount being created every 10 minutes. Big data tools are used by companies like eBay, Amazon, and Walmart to handle high volumes of customer transactions and queries, with some companies storing petabytes or more of data. Common big data software includes Hadoop, Spark, and Splunk, while real-world examples demonstrate big data's use in fields like healthcare, retail, and social