## The Source Area

The source area is for choosing an unit and entering values. After pressing a key, the value of source will be converted simultanously. and the text field called "target" will be updated immediately. In other words, there is no need to press the return key. A little flag will show you the country or countries, where your selected unit is used usually.

Flags
A little flags shows the country where the unit is used usually.

Flags | Description
| Système Internationale; SI-units or from the SI derived scientific units.
| International units, which are not SI units.
| used in Europe
| used in English spoken countries, like USA and UK
| used in USA
| used in UK
| used in France
| used in Spain
| used in Germany
... |

Fontcolor
A gray text in the combo box will show an obsolete unit or an unit which is no longer used in a particular country. Also unusual units have a gray color (e. g. "Dekameter"). If you want to add, modify or delete units and flags please have a look at the section "Units".