Fact retrieval refers to the retrieval carried out by users in order to determine the time, place and process of an event or fact.
Data retrieval means that users use some retrieval tools to find a certain numerical data. Its purpose is to find some deterministic data, and these data are numerical.
Document retrieval is a process of finding relevant documents that meet specific needs from a large number of document collections. Literature retrieval is the core part of information retrieval, which is richer in content and more diverse in methods than the following data retrieval and fact retrieval. According to the retrieval content, it can be divided into bibliographic retrieval and full-text retrieval. According to the object, it can be divided into book retrieval, periodical retrieval, patent retrieval, standard retrieval and dissertation retrieval. ...