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Few basic notices you must absolutely know about LibreAtlas databases

Technically speaking any LibreAtlas database simply is a SQLite db-file internally storing SpatiaLite and RasterLite tables.
In other world, it's like a big repository containing both vector and raster data. Don't be fussed by the word Spatial Database.
It's nothing too much complex; it simply is a useful system allowing to store and retrieve geographic informations in a quick and very efficient way, nothing more than this.

Spatial Is Not Special: geographic sofware simply is a specialized version of general purpose software, there isn't absolutely nothing magic or extraordinary in this.
Simply a very basic preliminary knoledge about general computing (and about Geography, quite obviously) is expected from you as a pre-requisite.

Any LibreAtlas database internally contains several datasets: some of them are of the vector type, others are of the raster type.
All them share anyway some common features. We'll now quickly examine several interesting facets, using the WorldAtlas as a specific reference.

Coordinate Reference System

The supported SRS always is WGS84, as formally identified by the EPSG standard SRID 4326.
This CRS is one of the geographic type, i.e. it's based on Latitude and Longitude measured angles.

Spatial Resolution (Nominal Scale)

The supported nominal scale for each dataset is one well fit for global world representations.
It typically is about 30 arc seconds, this roughly corresponding to 1 Km on the Equator.

Supported vector datasets

The following datasets (aka layers) of the vector type are always included on every LibreAtlas database:

Supported raster datasets

The following datasets (aka layers) of the raster type may be included on a LibreAtlas database (depending on actual version / configuration):

Visual Examples
datasetWorld CoverageRegional Detail
Political map (vector layers) political-map.png italy-political.png
Satellite map (TrueMarble) satellite-map.png italy-satellite.png
Relief map (SRTM30) relief-map.png italy-relief.png
Bathymetry map (ETOPO-1) bathymetry-map.png italy-bathymetry.png
Temperature map mtemp-jan-map.png
Precipitation (rain) map prec-apr.png

LibreAtlas database editions

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