BSD (Berkeley Software Distribution) was a Unix operating system developed at UC Berkeley. It introduced critical innovations including TCP/IP networking, the vi editor, and the BSD license that enabled open-source software.
Origins
The Berkeley Computer Systems Research Group, led by researchers including Bill Joy, began distributing modifications to Unix in 1977. These distributions included new utilities, improved performance, and eventually a complete operating system.
Key Innovations
BSD introduced fundamental computing technologies:
- TCP/IP stack: The networking code that powers the internet
- vi editor: Standard Unix text editor
- C shell (csh): Alternative command shell
- Fast File System (FFS): Improved file system performance
- Virtual memory: BSD’s VM implementation
TCP/IP and the Internet
BSD’s TCP/IP implementation, funded by DARPA, became the reference implementation of internet protocols. This code spread to virtually every operating system and enabled the internet’s growth.
BSD License
The BSD license allowed code to be used in proprietary products, unlike the GPL’s copyleft. This permissive approach enabled:
- macOS (derived from FreeBSD)
- PlayStation OS
- WhatsApp servers
- Many embedded systems