What are the two most common reference frames used worldwide?

The most common reference frames used globally are WGS84 and ITRF 2000.

WGS84 (World Geodetic System 1984) is a globally recognized reference frame, widely employed in GPS and various mapping applications. It provides a consistent framework for geolocation and is essential for various technological infrastructures that rely on accurate positioning.

ITRF 2000 (International Terrestrial Reference Frame) is another highly precise reference frame utilized for applications requiring exact measurements of the Earth's surface. It is particularly important in scientific research and various geospatial applications, as it reflects tectonic plate motions and updates its parameters periodically to maintain accuracy.

Both WGS84 and ITRF 2000 serve as foundational frameworks for geospatial data and are essential for ensuring interoperability in global navigation and mapping systems. This combination of reference frames allows for high-resolution positioning and accurate spatial analysis, which is crucial for numerous GIS applications.

Options featuring NAD27 (North American Datum of 1927) and NAD83 (North American Datum of 1983) are more region-specific and typically used for data within North America. NAVD88 (North American Vertical Datum of 1988) deals specifically with elevation data, making it less applicable to the broader context of