4.1. Big Data 1.0 (1994—2004)BigData1.0coincideswiththe adventof e-commercein 1994, duringwhich time online firmswere the main contributors of the web content. User-generated content was only a marginal part of web content due to the technical limitation of web applications. In this era, web mining techniques were developed to analyze users’ online activities. Web mining can be divided into three different types: web usage mining, web structure mining, and web content mining.