I have a polygon layer. I toggled to edit mode. I added a new column, while number (integer) and called it "area". I then use the field calculator - geometry - $area to populate the polygon area for my polgyons.
Under Layer Properties - first tab - the unit is millimetre
In metadata tab: Extents: In layer spatial reference system units : xMin,yMin 114.53,-38.7888 : xMax,yMax 153.639,-9.22883 Layer Spatial Reference System: +proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs
Can anyone tell me what the area is calculated in? km2, acres, hectares or what?