The PDP-11 is a series of 16-bit minicomputers developed by Digital Equipment Corporation (DEC) in the early 1970s. Known for its modular design and versatility, the PDP-11 became popular in both academic and commercial settings. It supported various operating systems, including Unix, which contributed to its widespread use. The architecture of the PDP-11 allowed for multiple addressing modes and a rich instruction set, making it suitable for a range of applications. Its influence can still be seen today, as many modern computer architectures have been inspired by its design principles.