This chapter describes some terms and abbreviations used in this document.
ACPI
Advanced Configuration and Power Interface, an industry specification for BIOS and hardware extensions
to configure PC hardware and perform power management. Windows 2000 and later, as well as Linux 2.4 and later
support ACPI. Windows can only enable or disable ACPI support at installation time.
AHCI
Advanced Host Controller Interface, the interface that
supports SATA devices such as hard disks. See
Hard Disk Controllers.
API
Application Programming Interface.
APIC
Advanced Programmable Interrupt Controller, a newer version of
the original PC PIC (programmable interrupt controller). Most
modern CPUs contain an on-chip APIC, called a local APIC. Many
systems also contain an I/O APIC (input output APIC) as a
separate chip which provides more than 16 IRQs. Windows 2000
and later use a different kernel if they detect an I/O APIC
during installation. Therefore, an I/O APIC must not be
removed after installation.
ATA
Advanced Technology Attachment, an industry standard for hard disk interfaces
which is synonymous with
IDE. See
Hard Disk Controllers.
BIOS
Basic Input/Output System, the firmware built into most personal computers which is
responsible of initializing the hardware after the computer has been turned on and
then booting an operating system. Oracle VirtualBox ships with its own virtual BIOS
that runs when a virtual machine is started.
COM
Microsoft Component Object Model, a programming infrastructure for modular software.
COM enables applications to provide application programming interfaces which can be
accessed from various other programming languages and applications.
Oracle VirtualBox makes use of COM both internally and externally to provide a
comprehensive API to third party developers.
DHCP
Dynamic Host Configuration Protocol. This enables a networking device in a network to
acquire its IP address and other networking details automatically, in order to avoid
having to configure all devices in a network with fixed IP addresses.
Oracle VirtualBox
has a built-in DHCP server that delivers an IP addresses to a virtual machine when networking
is configured to NAT. See
Virtual Networking.
EFI
Extensible Firmware Interface, a firmware built into computers which is designed to replace
the aging BIOS. Originally designed by Intel, most modern operating systems can now boot
on computers which have EFI instead of a BIOS built into them.
See
Alternative Firmware (EFI).
EHCI
Enhanced Host Controller Interface, the interface that implements the USB 2.0 standard.
GUI
Graphical User Interface. Commonly used as an antonym to a "command line interface".
In the context of Oracle VirtualBox, we sometimes refer to the main graphical
VirtualBox program as the "GUI", to differentiate it from the VBoxManage interface.
MAC
Media Access Control, a part of an Ethernet network card. A MAC address
is a 6-byte number which identifies a network card. It is typically written
in hexadecimal notation where the bytes are separated by colons,
such as 00:17:3A:5E:CB:08
.
MSI
Message Signaled Interrupts, as supported by modern chipsets such as
the ICH9. See
Motherboard Tab. As opposed to traditional
pin-based interrupts, with MSI, a small amount of data can accompany
the actual interrupt message. This reduces the amount of hardware pins
required and allows for more interrupts and better performance.
NAT
Network Address Translation. A technique to share networking interfaces
by which an interface modifies the source and/or target IP addresses of
network packets according to specific rules. Commonly employed by routers
and firewalls to shield an internal network from the Internet,
Oracle VirtualBox can use NAT to easily share a host's physical
networking hardware with its virtual machines.
See
Network Address Translation (NAT).
PAE
Physical Address Extension. This enables access to more than 4 GB
of RAM, even in 32-bit environments. See
Advanced Tab.
PXE
Preboot Execution Environment, an industry standard for booting
PC systems from remote network locations. It includes DHCP for IP
configuration and TFTP for file transfer. Using UNDI, a hardware
independent driver stack for accessing the network card from bootstrap
code is available.
RDP
Remote Desktop Protocol, a protocol developed by Microsoft as an
extension to the ITU T.128 and T.124 video conferencing protocol.
With RDP, a PC system can be controlled from a remote location
using a network connection over which data is transferred in
both directions. Typically graphics updates and audio are sent
from the remote machine and keyboard and mouse input events are
sent from the client. An
Oracle VirtualBox extension package by
Oracle provides VRDP, an enhanced implementation of the relevant
standards which is largely compatible with Microsoft's RDP
implementation.
See
Remote Display (VRDP Support) for details.
SCSI
Small Computer System Interface. An industry standard for data
transfer between devices, especially for storage. See
Hard Disk Controllers.
SMP
Symmetrical Multiprocessing, meaning that the resources of a
computer are shared between several processors. These can either
be several processor chips or, as is more common with modern
hardware, multiple CPU cores in one processor.
SSD
Solid-state drive, uses microchips for storing data in a computer
system. Compared to classical hard-disks they have no mechanical
components, such as spinning disks.
TAR
A widely used file format for archiving. Originally, this stood for Tape ARchive
and was already supported by very early UNIX versions for backing up data on
tape. The file format is still widely used today. For example, with OVF archives
using an
.ova
file extension.
See
Importing and Exporting Virtual Machines.
UUID
A Universally Unique Identifier, often also called GUID (Globally Unique Identifier).
A UUID is a string of numbers and letters which can be computed dynamically and is
guaranteed to be unique. Generally, it is used as a global handle to identify entities.
Oracle VirtualBox makes use of UUIDs to identify VMs, Virtual Disk Images (VDI files),
and other entities.
VM
Virtual Machine. A virtual computer that
Oracle VirtualBox enables
you to run on top of your actual hardware.
See
Some Terminology for details.
VRDE
VirtualBox Remote Desktop Extension. This interface is built into
Oracle VirtualBox to allow
Oracle VirtualBox
extension packages to supply remote access to virtual machines. An
Oracle VirtualBox extension
package by Oracle provides VRDP support.
See
Remote Display (VRDP Support).
xHCI
eXtended Host Controller Interface. The interface that implements the USB 3.0 standard.
XML
The eXtensible Markup Language, a metastandard for all kinds of
textual information. XML only specifies how data in the document
is organized generally and does not prescribe how to semantically
organize content.
XPCOM
Mozilla Cross Platform Component Object Model, a programming infrastructure
developed by the Mozilla browser project which is similar to Microsoft COM
and enables applications to provide a modular programming interface.
Oracle VirtualBox makes use of XPCOM on Linux both internally and
externally to provide a comprehensive API to third-party developers.