In some contexts, such as research environments, a popular way of classifying databases is according to the type of
data stored in them. Using this criterion, databases are grouped into two categories: general-purpose and disciplinespecific
databases. General-purpose databases contain a wide variety of data used in multiple disciplines—for
example, a census database that contains general demographic data, and the LexisNexis and ProQuest databases that
contain newspaper, magazine, and journal articles for a variety of topics. Discipline-specific databases contain
data focused on specific subject areas. The data in this type of database are used mainly for academic or research
purposes within a small set of disciplines. Examples of discipline-specific databases include financial data stored in
databases such as CompuStat or CRSP, geographic information system (GIS) databases that store geospatial and other
related data, and medical databases that store confidential medical history data.