> For the complete documentation index, see [llms.txt](https://docs.smartglobe.cadac.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.smartglobe.cadac.com/smartglobe-rembrandt/glossary.md).

# Glossary

The following terms and their definitions are used throughout the smartGlobe Rembrandt application.

| Abeam location      | (*passing* point) the point at which an airplane, following a certain track, passes a beacon at a 90° angle.                                                                                                                       |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| AIRAC cycle         | A 28-day administrative cycle for update of aeronautical information.                                                                                                                                                              |
| ARINC 424           | Navigation Data standard file format, developed for Flight Management Systems.                                                                                                                                                     |
| Chart               | A graphical representation (to scale or not to scale) of geographical and/or aeronautical objects in a MicroStation (design) file.                                                                                                 |
| Chart Footprint     | The definition of geographical area (latitude/longitude boundaries), scale, grid or graticule and frame size which is defined for each individual chart.                                                                           |
| Effective Date      | Calendar data on which a static data change comes into effect.                                                                                                                                                                     |
| Frame (size)        | Rectangle, representing the boundaries of the chart.                                                                                                                                                                               |
| Greatcircle         | If an intersecting plane passes through the centre of the sphere, the resulting section is a circle whose radius is the largest which can occur (equal to the radius of the sphere itself). This circle is called the greatcircle. |
| Feature             | A group of (database) aeronautical objects of the same type, e.g. VOR, DME, NDB and TACAN together form the ingredient ‘Navigation Aid’.                                                                                           |
| Label               | (Annotation label) A graphical element which is linked to an aeronautical object in a chart, and which can contain database attributes for that element.                                                                           |
| Lambert projection  | Projection, based on a vertical conical shape, intersecting the ellipsoid at two parallels.                                                                                                                                        |
| Mercator projection | Projection, based on a vertical cylindrical shape, intersecting the ellipsoid at one parallel.                                                                                                                                     |
| Polar projection    | Azimuthal projection, based on a flat surface intersecting the ellipsoid at the pole.                                                                                                                                              |
| Rhumbline           | A rhumbline is defined as the curve that intersects the meridians at a constant angle.                                                                                                                                             |
| Tick mark           | A small division mark on a grid reference line or chart’s border.                                                                                                                                                                  |