As with open source software, open source hardware is about having the freedom to study, share and modify designs, and to sell products that are built using those designs.
While the open source hardware movement is earlier in its development than the open source software movement, it is growing at a rapid pace and is set to have a profound effect on hardware innovation and many technologies that we use every day.
Designs are published under a Creative Commons Attribution licence, which allows for both personal and commercial derivative works, as long as credit is provided.