Autodesk EAGLE

CadSoft EAGLE is commercial software for editing circuit schematics, PCB layouts and component libraries. It is available for Windows, Linux and OS X.

Editions
The Light Edition can be used for free but is limited to boards of 100 x 80 mm (4 x 3.2 inches), only two signal layers (top and bottom) and the schematic editor can only create one sheet. It can however Load, view and print drawings that exceed these limits.

To edit the most commonly used Eurocard size 100 x 160 mm (4 x 6.4 inches) would require the EAGLE Hobbyist edition, (for individual, non-commercial use only) which costs $169.