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NAD83(HARN) – EPSG:4152 is a high-precision realization of the North American Datum of 1983 (NAD83), developed through the High Accuracy Reference Network (HARN) program by the U.S. National Geodetic Survey in the 1990s. By incorporating GPS observations, it improved positional accuracy to approximately 0.01–0.05 meters, significantly better than the original NAD83. While superseded by newer realizations, it remains widely used in legacy GIS data and local government applications across the United States.

ITRF2005 (International Terrestrial Reference Frame 2005) is one of the international terrestrial reference systems, established by the International Earth Rotation and Reference Systems Service (IERS). ITRF2005 is a three-dimensional terrestrial coordinate system generated by integrating data from multiple space geodetic techniques, including GPS, VLBI, SLR, and DORIS. It defines the positions of observation points on the Earth's surface and their temporal changes with high precision. ITRF2005 adopts an Earth-Centered, Earth-Fixed (ECEF) coordinate system and is a dynamic reference frame that accounts for temporal changes such as crustal deformation and plate motion. It is widely used in GIS, satellite positioning, Earth science research, and other fields, and is registered under EPSG code EPSG:4896.

ITRF2008 (International Terrestrial Reference Frame 2008) is an international three-dimensional terrestrial reference system constructed based on global geodetic observation data. Published by the International Earth Rotation and Reference Systems Service (IERS), which oversees global geodesy and Earth rotation observations, it is one of the international reference frames created by integrating multiple space geodetic techniques such as GNSS, VLBI, SLR, and DORIS. ITRF2008 is defined as a three-dimensional Cartesian coordinate system (X, Y, Z) with its origin at the Earth’s center, enabling high-precision positioning that accounts for plate motion and crustal deformation. It is widely used as a reference frame in many satellite positioning systems and international geodetic networks, forming the foundation for Earth science research and high-precision positioning. In EPSG, it is defined as EPSG:5332.

WGS84 / Pseudo-Mercator (EPSG:3857) is a projected coordinate system widely used in modern web mapping services. It is based on the WGS 84 geographic coordinate system and employs a simplified version of the traditional Mercator projection adapted for web display. Primarily designed for rendering tile-based web maps, it serves as the standard display coordinate system for online map services and GIS platforms. By converting geographic coordinates expressed in degrees to plane coordinates in meters, it facilitates fast map rendering and zooming operations.

WGS84 (G1674) is one of the updated realizations of the globally used World Geodetic System 1984 (WGS84), a frame that has been improved in accuracy based on GNSS observation data. The EPSG code EPSG:4979 defines a three-dimensional geographic coordinate system that represents a position using three components: latitude, longitude, and ellipsoidal height. WGS84 (G1674) is primarily used in global navigation satellite systems and is widely employed as the positioning reference, especially for GPS. Based on an Earth-Centered, Earth-Fixed (ECEF) framework and using an Earth ellipsoid model, it enables highly accurate representation of positions on the Earth's surface.

Pulkovo 1942 / Gauss–Krüger projection is a combination of a geodetic datum and a projection method widely used in the former Soviet Union and Eastern Europe. Pulkovo 1942 is a national geodetic datum established by the Soviet Union, adopting the Krasovsky ellipsoid as its reference ellipsoid. The Gauss–Krüger projection is a transverse Mercator projection that converts the Earth's surface into plane coordinates using longitudinal zones. This combination was used for decades in topographic mapping, military surveying, cadastral surveying, and other applications across the former Soviet republics.

Tokyo UTM Zones are historic projected coordinate systems applying the UTM projection to the Tokyo datum (Bessel 1841 ellipsoid), serving as Japan's fundamental geodetic framework until 2002. While modern systems like JGD2000/JGD2011 UTM zones have superseded them, these zones remain essential for interpreting 20th-century Japanese geographic data.

Sri Lanka Kandawala Grid is a historic projected coordinate system based on the Kandawala datum, established during the British colonial period to serve as the foundational mapping framework for the island nation. Developed in the early 20th century, this system employs a transverse Mercator projection to support cadastral surveying, topographic mapping, and engineering projects throughout Sri Lanka. While modern systems like SLD99 / Sri Lanka Grid 1999 (EPSG:5235) have been introduced for contemporary applications, the Kandawala Grid remains essential for interpreting the extensive archive of 20th-century geographic data across the country.

Madagascar Laborde Grid is a historic oblique Mercator projection system designed in 1926 by French engineer Jean Laborde specifically for Madagascar's unique geography. Based on the Tananarive datum, it remains the legally mandated projection for the island nation.

South Africa Lo System (Lo System, short for "Landmeter-generaal Lo-sone" or "Surveyor-General Lo zones") is a suite of projected coordinate systems established by the Office of the Surveyor-General of South Africa to serve as the foundational mapping framework for the country. Developed as a national standard, this system employs a transverse Mercator projection divided into multiple 2° longitude-wide belts to support cadastral surveying, engineering projects, and topographic mapping throughout South Africa. While modern implementations like Hartebeesthoek94 / Lo zones (EPSG:2050-2058) provide WGS84-compatible alternatives, the historical Cape / Lo zones (EPSG:22275-22293) remain essential for interpreting the extensive archive of 20th-century geographic data across South Africa .