The open source movement changed how companies build software. Facebook, Twitter, and Yahoo employees pitched in during the early days of the data-crunching software Hadoop. Even after the relationship between Apple and Google soured, the companies' coders kept working together on an obscure but important piece of software called LLVM. Microsoft now uses and contributes to the Linux operating system, even though it competes with Windows.

The embrace of open source isn't about altruism. Facebook started using Hadoop because there was no commercial off-the-shelf software that met the company's needs as it grew. Because Hadoop is open source, Facebook could customize and extend it to solve its specific problems; sharing its changes allowed others to innovate further, making the software better for Facebook and all other users. Collaborating on freely available code enables companies and programmers to pool resources to solve common problems and avoid reinventing the wheel. Companies build competing products and services from these open source foundations that they might never have been able to build otherwise.

But the open source revolution has been slow to come to the hardware world. A number of open source gadgets and circuit boards have been released in recent years, but while it's possible to run a laptop or server on nothing but open source software, the inner workings of our gadgets remain proprietary.

An open source chip architecture called RISC-V could soon help change that. Chip maker Nvidia and storage company Western Digital have both announced plans to use RISC-V chips in their core products, and dozens of other companies have joined the RISC-V Foundation, including Google, Tesla, and chip giants like IBM, Samsung, and Qualcomm. RISC-V isn’t the first open source chip architecture, but it’s unusual for such a project to attract much attention outside of academia.

David Patterson, a computer architecture pioneer and vice chair of the board of the RISC-V Foundation, hopes RISC-V will lead to the creation of faster, more efficient, and more secure chips. Chip makers could, for example, collaborate to solve sticky problems like Spectre, the nightmarish security flaw that affects virtually all computer and smartphone chips. "The problem with proprietary architectures is that you have to work for the company, whether that's Intel, AMD, or Arm, if you want to improve on the designs," Patterson says. "The Spectre problem is a difficult challenge in computer architecture, what we need is everyone working on it."

RISC-V isn't a design for a full chip. It's what's called an "instruction set architecture," which Patterson describes as the "vocabulary" that hardware and software use to talk with each other. RISC-V is a common vocabulary that all chip makers can use when building their chips. It includes a core set of instructions and optional instructions that a chip maker can add, depending on the needs of a particular chip.

RISC, which is short for "reduced instruction set computing," is the concept of using streamlined, minimal vocabularies in chip design. Patterson helped pioneer the concept at the University of California, Berkeley in the early 1980s, and his team coined the term. But early academic work on RISC didn't define a complete instruction set. In 2010, a group of professors at Berkeley created their own RISC instruction set to use in class. That eventually evolved into an ongoing project that attracted the attention of the technology industry, so they put together the RISC Foundation to manage the project.

Patterson thinks RISC-V will be useful in creating more specialized types of chips, as opposed to the one-size-fits-all central processing units made by companies like Intel. Specialized chips aren't new---Nvidia has been selling specialized graphics chips since the 1990s---but the idea has taken off in recent years as companies explore artificial intelligence and try to pack more computational power into everything from cars to barbecue grills. For example, Google uses its "Tensor Processing Units" (TPUs) in its data centers, and its Pixel 2 phone contains a custom chip called the Visual Core that powers the gadget's camera.