Multi-port buses and Point to point Ports.
  Legacy serial port.  RS-232 (3600 baud or 400 bytes/sec)
    Modems, terminal, mice, printers, etc.

  Legacy parallel port  IEEE 1284.
    Printers - Centronics, Zip drives

  S100 - 1974 - Altair 8800 (Intel 8080 CPU) 1st? standardized PC bus. 
    Back-pane bus (even the CPU was on interface card).
 
  IEEE 488 Parallel bus. (HP design)
    Plotters, scientific measuring devices.

  XT and AT (PC) bus - original bus for the IBM PC.

  ISA (Industry Standard Architecture) - generic version of PC bus.

  MCA (32 bit Micro-channel architecture) - wider bus, improved speed and 
     control. Supported a type of Plug and Play.
       (Proprietary - required licensing from IBM).

  EISA (Extended) - 32 bit wide data bus, improved speed and control.
       (Open source competitor to MCA - many similar features)
       EISA connectors on motherboards were designed to also take ISA.

  NuBus - (~1987) 32 bits bus designed to be CPU "agnostic". Simple, flexible
    design, early 'Plug and Play' but this put burden on interface card and
    driver software. Macintosh II * superseded by PCI

  Local bus - VLB (VESA video local bus) - Early attempt to provide a
    non-proprietary local bus for high speed i/O and memory access such as 
    video and DMA for hard drives. Level 2 cache also attached here.
    Used with Intel 486 CPU systems. Too tightly coupled to 486.
  
  PCI (Peripheral Component Interconnect) - wider, faster, greatly
       improved control. Protocol governed by independent body but Intel 
       manufactures most of the logic chips needed to make it work.

  AGP (Advanced graphics port, modified PCI) - used to connect a time/data 
    critical devices, usually the video card. (Replace VLB).
    Tweaked version of PCI that offered faster throughput.
    Treated as a point to point connection.
      Several versions : 1.0, 2.0, 3.0, 3.5. 
      Voltage levels : 1.5, 3.3 and .8 volts.
      Speeds : 33 MHz, 66 MHz. 
    * replaced by PCIe in current systems (2010) 
 
  PCIe (PCI-express) - PCI protocol provided over isolated serial connections
    to each device. Much higher data throughput. Most address and control 
    handled by the PCIe controller. Data and device control/status using data 
    packets. 

  SCSI (small computer systems interface) - multiport (8,16) agnostic bus
    for higher speed drives and devices. Usually required an interface to
    the systems primary bus.

External/between control cards and hardware devices (hard drive, Cd-ROM)

  PATA-IDE - bus designed specifically for hard drives then expanded to work
    with other storage devices (CD, DVD). Allows 4 devices per cable but
    usually only implemented with 2.

  SATA - replaced separate physical buses (address, data, control) with
    virtual buses over pairs of lines. Information send serially at very
    high speeds.  All connections between controller and device 1 point to 
    point but controller can talk to several devices.

  e-SCSI - protocol/connections that allow connection to external drives.

  USB (universal serial bus) - simple physical bus using serial interface 
    (D+/D-), and when power provided, 2 additional lines (power,ground) used.
    Multi-tasks data lines to provide address, data, and control functions.

  Fire-wire - serial bus (SCSI).  Similar to USB.
    Independent of specific devices.