"A geographic information system (GIS) consists of integrated computer hardware and software that store, manage, analyze, edit, output, and visualize geographic data."
Researching the geographic locations associated with ancestors, including historical maps, gazetteers, and other resources to help identify the locations.
World Geography: Understanding the geographic layout of the world, countries, and major cities that have an impact on genealogy research, will help in analyzing geographic data.
Historical Geography: Knowledge of the geo-political, cultural and social aspects of an area in history, this helps to understand how the settlement patterns, migration, and immigration patterns evolved from time to time.
Cartography: Understanding different types of maps, how they are made, and locating places use map features to understand genealogy research through the integration of geo-information with historical data.
Spatial Analysis: A geographic information system used to analyze statistical data, spatial patterns and develop new methods to understand the genealogical data.
Genealogy Research Methodology: Understanding research methodologies for genealogy and demographic analysis to improve place-based research techniques.
Demographic Data: Population data for an area can help in understanding the population's makeup in the past and evolution of the population movements, migration patterns, and leads to the identification of ancestral records.
Land Records and Property Data: Using property records to understand land usage, family history, and ancestral records analyses can establish residency, migration, and ancestral connections.
Census Records: Census records are an essential resource to identify and locate ancestral records that helps in genealogy research.
Toponymy: Understanding the origin and meaning of geographical names which enable the identification of places from which people migrated.
DNA Analysis: Understanding how genealogy research has evolved through DNA testing techniques, including allele patterns, genetic mapping, and forensic analysis of ancestral records.
Cultural Geography: Understanding how cultural practices, traditions, and language patterns evolved and impacted genealogy research.
Preservation of Genealogy Data: Methods of record-keeping and the appropriate methods to preserve genealogy data for future reference.
Pedigree research: Tracing an individual’s direct ancestry.
Descendant research: Tracing the descendants of an individual.
Family group research: Tracing all members of a particular family.
One-name study: Researching all people with a particular surname.
DNA analysis: Using DNA to identify relationships between people and trace ancestry.
Emigration and immigration research: Tracing the movement of families from one country to another.
Heir searching: Tracing living relatives to establish legal rights or claim to inheritance.
Military research: Tracing military service history of individuals.
Social history research: Researching the social context in which ancestors lived.
Local history research: Researching the history of a specific place and the people who lived there.
"[A GIS] consists of integrated computer hardware and software that store, manage, analyze, edit, output, and visualize geographic data."
"Much of this often happens within a spatial database, however, this is not essential to meet the definition of a GIS."
"One may consider such a system also to include human users and support staff, procedures and workflows, the body of knowledge of relevant concepts and methods, and institutional organizations."
"The uncounted plural, geographic information systems, also abbreviated GIS, is the most common term for the industry and profession concerned with these systems."
"The academic discipline that studies these systems and their underlying geographic principles, may also be abbreviated as GIS, but the unambiguous GIScience is more common."
"They are attached to various operations and numerous applications, that relate to: engineering, planning, management, transport/logistics, insurance, telecommunications, and business."
"GIS and location intelligence applications are at the foundation of location-enabled services, which rely on geographic analysis and visualization."
"GIS provides the capability to relate previously unrelated information, through the use of location as the 'key index variable'."
"Locations and extents that are found in the Earth's spacetime are able to be recorded through the date and time of occurrence, along with x, y, and z coordinates."
"[x, y, and z coordinates representing] longitude (x), latitude (y), and elevation (z)."
"All Earth-based, spatial-temporal, location and extent references should be relatable to one another, and ultimately, to a 'real' physical location or extent."
"This key characteristic of GIS has begun to open new avenues of scientific inquiry and studies." Note: Since not all 20 questions can be answered directly by quotes from the paragraph, I have provided answers for the available quotes.