Nubus is a computer architecture and a type of expansion slot designed for plug-in cards, such as video and network cards. It was introduced by Apple in 1987 and used in their Macintosh II computer line. The technology was designed for easy installation of hardware, but has been largely replaced by newer interfaces like PCI and PCI Express.


The phonetics of the keyword “Nubus” is: /’nu:bʌs/

Key Takeaways

  1. Nubus is a 32-bit parallel computer bus, which is essentially a set of wires used for transmitting data between computer components or between computers. It was created by Texas Instruments and used in Apple Macintosh II and NeXT computers among others.
  2. Another feature of Nubus is its architecture. Unlike many of its contemporaries, Nubus did not utilize a common shared bus. Instead, it made use of a protocol that could understand multiple completely different types of traffic, including for both memory-mapped I/O and block transfers.
  3. Nubus was largely displaced in desktop computers by Intel’s PCI in the mid-1990s, due to PCI’s greater speed and versatility. However, the Nubus design has had a lasting impact, influencing the design of later bus systems.


NuBus is significant in the field of technology as it was a precursor to modern bus architectures used in computers. Developed at MIT in the 1980s, NuBus was a 32-bit parallel computer bus that became a key feature of Apple’s Macintosh II, which was the first expandable Macintosh model. NuBus slots allowed for the easy addition of devices or expansion cards without the need for complex configuration, representing a major advancement in user-friendliness. This system stands as an important milestone in computer technology, demonstrating a move towards ease-of-use and expandability that has greatly influenced subsequent computer design.


Nubus is a technology term that refers to a specific type of bus architecture utilized in Apple Macintosh computers during the late 1980s to mid 90s. It was a 32-bit parallel computer bus, originally developed at MIT, and was incorporated into the Mac II by Apple as the main way to connect peripheral devices to the computer. The key purpose of the Nubus was to allow for the seamless addition of peripheral devices by easily plugging in Nubus cards into the Nubus slots on the motherboard, improving the computer’s flexibility and scalability. These devices could range from network cards and video cards to hard drives and more.The unique aspect of Nubus was its protocol, which enabled it to automatically recognize and configure new hardware, thereby allowing for quicker, more efficient ‘plug and play’ of devices. This automatic configuration, often called “self-identifying”, was an advance over earlier PC buses which required more manual setup. Thus, Nubus technology was particularly beneficial for increasing the usability of the computer and eliminating many technical hassles in expanding its capabilities. However, over time, Nubus was phased out in favor of newer technologies like PCI which offered faster data transfer rates.


NuBus is a technology standard for computer add-on cards and expansion slots. It was popularized during the late 1980s and 1990s, especially within the Apple Macintosh ecosystem. Here are three real-world examples:1. The Apple Macintosh II: This was one of the first personal computers to make extensive use of the NuBus technology. The Macintosh II had multiple NuBus slots, allowing users to add several plug-in boards such as video, memory or network cards.2. NuBus Video Cards: An example of a NuBus add-on card would be the Radius full-page display cards created for the Macintosh II, which enabled users to add additional external monitors thereby increasing the amount of screen real estate they could use.3. NuBus Network Cards: Networking was another common use of NuBus technology. Cards such as the Apple EtherTalk NB Card was used to give Macintosh computers the ability to network with each other, share resources and access the Internet.

Frequently Asked Questions(FAQ)

Q: What is Nubus?A: Nubus is a 32-bit parallel computer bus, initially developed at MIT and standardized in 1987 as a part of the NuMachine workstation project. This was the first plug-and-play bus from Apple Computer.Q: What does Nubus stand for?A: Nubus doesn’t actually stand for anything. Despite popular belief, it’s not an acronym, but a name chosen for its unique sound and connotation.Q: What was the primary purpose of Nubus?A: Nubus was originally designed to add expansion cards to Apple Macintosh computers. It was meant to enhance things like graphics capabilities, sound devices, network interfaces, and other system upgrades.Q: Who developed Nubus?A: Nubus was a product of the Massachusetts Institute of Technology (MIT) and was later adopted and standardized by Apple for their computers.Q: Was Nubus exclusively for Apple products?A: Initially, yes. It was designed for the Macintosh platform. However, it was eventually adapted for a few other systems, including early NeXT machines and Texas Instruments’ NuBus-based Explorer Lisp machines.Q: What replaced Nubus?A: Nubus was replaced by Peripheral Component Interconnect (PCI) in the mid-1990s. PCI provided a more universal standard with faster speeds, which eventually made Nubus obsolete.Q: Can I still use Nubus on modern computers?A: Most modern computers don’t support Nubus because the technology is no longer maintained or manufactured, and has been superseded by newer interfaces. However, some vintage computer enthusiasts continue to use and experiment with Nubus on older machine models.Q: How does Nubus compare to other computer buses of its time?A: Nubus was well-regarded in its time for its then-advanced plug-and-play functionality, where peripherals could be added or removed without having to set DIP switches or jumpers on the cards. However, its slower speed compared to newer technology like PCI eventually led to its displacement.

Related Tech Terms

  • Micro Channel Architecture
  • Data bus
  • Peripheral Component Interconnect (PCI)
  • Expansion slot
  • Information Processing Architecture (IPI)

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