Simply stated, Business Intelligence is analysis of business data. BI is the name given to software tools specifically designed to aid analysis of business data. BI tools have traditionally been associated with in-depth analysis of historical transaction data, supplied by either a data warehouse or an online analytical processing (OLAP) server linked to a database system. BI has a wide range of  applications, with the most common being the analysis of patterns such as sales and stock trends, pricing and customer behavior to inform business decision-making. For this reason it is sometimes referred to as decision support software.