Data mining is the process of discovering potentially useful, interesting, and previously unknown patterns from a large collection of data. The process is similar to discovering ores buried deep underground and mining them to extract the metal. The term "knowledge discovery" is sometimes used to describe this process of converting data to information and then to knowledge.

Data, Information, and Knowledge

Data are any facts, numbers, or text that can be processed by a computer. Many organizations accumulate vast and growing amounts of data in a variety of formats and databases. These data may be loosely grouped into three categories: operational or transactional data, such as company sales, costs, inventory, payroll, and accounting; non-operational data, such as industry sales, forecast data, and macro-economic data; and metadata, which is data about the data themselves, such as elements related to a database's design or query protocol...