Fritzing is a Electronic Design Automation Software. It is an open-source initiative to support designers, artists, researchers and hobbyists to take the step from physical prototyping to actual product. We are creating this program in the spirit of Processing and Arduino, developing a software that allows users to document their Arduino and other electronic-based prototypes, share them with others, teach electronics in a classroom, and to create a pcb layout for manufacturing.
Fritzing is essentially an Electronic Design Automation program with a low entry barrier, conformable for the needs of designers and artists. It uses the metaphor of the breadboard, so that it is easy to transfer your hardware sketch to the software. From there it is possible to create PCB layouts for turning it into a robust PCB yourself or by help of a manufacturer.
Physical prototyping tools have come a long way and already allow non-engineers to quickly turn their ideas into functional interactive prototypes. However, the prototypes in this stage are still raw and not robust. This is where Fritzing comes in: It allows the designer to move to the next stage and create a finished PCB of your individual circuit in the desired shape. This makes the circuit robust and is the basis for a permanent installation or even batch production of your project.

The license of this software is Free, you can free download and free use this cad software.