What is JOSM

JOSM is the main offline editor for OpenStreetMap. All you need to run it is a current version of Java. Just load GPS tracklogs (.GPX files) into JOSM and start adding streets to OpenStreetMap instantly.

Read more at JOSM wikipage or go directly to the homepage

Dowload the latest version of JOSM here.

My tip for using JOSM; When selecting, holding down ALT while draging will make it easier to select things with the “bounding box”, if you select to much hold down ALT-CTRL instead to deselect.

Edit by Lambertus: update links