Open source hardware, also called open hardware, is electronic or computer hardware built from design information that could be copyrighted or licensed but has instead been made available for public use at no charge. Such information can include documentation, schematic diagrams, construction details, parts lists and logic designs.
In a literal sense, physical objects do not lend themselves to the open source paradigm in the same way as does software (with the possible exception of self-replicating robots). The term open source can, however, be applied directly to information that allows people to build, modify and update specific hardware items such as personal computers, computer peripherals, telecommunicationss.
In recent years, specialized software known as hardware description language (HDL) has become available for the design and engineering of hardware. Programs written in HDL can be copyrighted, just as can any other type of software. When HDL programs are made freely available, they can be considered open source hardware.