Open source hardware refers to computer and electronic hardware that is designed in the same fashion as free and open source software (FOSS). Open source hardware is part of the open source culture that takes the open source ideas to fields other than software.

The term has primarily been used to reflect the free release of information about the hardware design, such as schematics, bill of materials and PCB layout data, often with the use of FOSS to drive the hardware.

With the rise of reconfigurable programmable logic devices, the sharing of logic designs is also a form of open source hardware. Instead of sharing the schematics, hardware description language (HDL) code is shared. HDL descriptions are commonly used to set up system-on-a-chip systems either in field-programmable gate arrays or directly in application-specific integrated circuit designs. HDL modules, when distributed, are called semiconductor intellectual property cores, or IP cores.