Overview
In modern computers the operating system consists of the system
software that "makes the hardware usable" and provides shared
components to application software. The operating system normally
"comes with" the computer. In the Amiga, like on other computers,
the operating system consists of a part that is loaded from disk
(floppy disk or hard disk), and a part which is stored in higher
speed and/or read only memory (e.g. ROM or PROM chips on the
computer motherboard).
CAOS, Tripos and AmigaDOS
According to the original plans, the Amiga hardware was to be
accompanied by CAOS, which stood for "Commodore Amiga Operating
System", and was to be built on top of lower-level components like
Exec. Instead of CAOS, which never made it to a shipping version,
a British research project known as Tripos (named after the chair
where Cambridge University exam candidates had to sit), designed
by Tim King, was ported to the Amiga, and became "AmigaDOS".
When the Amiga was launched, in 1985, operating systems, and
the word "operating system" itself, while well known to computer
science students, did not have as strong an identity and
recognition to the broad audience as they would have in the
following decades. Even for the 1985 Byte Magazine Amiga article (included
in Amiga Forever), which introduced the Amiga to the masses, the
Amiga and its operating system were simply... the "Amiga". (The
article also uses terms like "disk operating system" and
"desktop", referring to the Workbench interface, but not
"AmigaDOS" or "operating system".)
In the 1980s the Amiga operating system consisted of a part
that was stored in ROM or on a disk called "Kickstart", and of
another part which was stored on a disk called "Workbench".
From AmigaDOS to Amiga OS
At some point it must have become clear that the "DOS" part of
"AmigaDOS" was somewhat of an understatement for an operating
system which comprised not only a "disk" part, but also
substantial multitasking, multimedia and other components. Also,
"DOS" brought to mind IBM and Microsoft's much less sophisticated
"DOS". So it comes that at Cloanto we have both original
"AmigaDOS" documentation from 1985 and 1986 stating that "AmigaDOS
is a multi-processing operating system designed for the Amiga",
and written developer's documentation by Commodore saying that
"AmigaDOS" should not be used to refer to the name of the Amiga
operating system.
Slowly, "Amiga OS" became used to refer to the Amiga operating
system as a whole, while "AmigaDOS" and "DOS" became used more
specifically for the disk subsystem. Computer users in general
became better aware of what an "operating system" was, and
recognized "OS" as its abbreviation.
In light of the historical roots of the Amiga operating system
(neither "CAOS" not "Tripos" had a "disk" part in them), and of
subsequent official company decisions and popular use, we consider
the brief use of "AmigaDOS" a small distortion of DOS-dominated
times more than the official operating system name meant to last
in the eyes of "Classic" Amiga history. Therefore "Amiga OS",
which is both generic and formally correct, appears to be a
better name to use in the context of the "Classic" Amiga
operating system, as used since 1985.
"Amiga OS" (with a space between
"Amiga" and "OS") is generally not used within the context of
Amiga Forever, which gives preference to the term "Workbench" to
identify the operating system.
From Amiga OS to AmigaOS
While other companies too use "OS" as a stand-alone word in
their operating system names (e.g. Apple, for "Mac OS"), somebody
possibly decided that "OS" in itself, meaning "operating system",
was too generic. It so occurred that Amiga OS 4.0 officially
became... AmigaOS 4.0, and a new name and distinctive trademark
was born.
"AmigaOS" (without spaces) is not used within the context of
Amiga Forever, which focuses entirely on "Classic" Amiga
systems, and is unrelated to the newer AmigaOS 4.0 project. To
better stress this difference and avoid any possibility of
confusion, Amiga Forever uses the word "Workbench".
Workbench
The name "Workbench" was originally not meant to
express the concept of an "operating system" as in "OS" or
"DOS". Nevertheless, perhaps also because of the lack of
branding clarity about what ought to have been the "real" name
of the Amiga operating system, and because of Cloanto's
increasing use of this word in Amiga Forever, "Workbench" kept receiving an
increasing preference by the public.
As released by Commodore, "Workbench" is both the name
of the Amiga desktop environment, which provides graphical user
interface access to files, programs and system settings, and the
name of the floppy disk which can be used to boot into the
Workbench environment. Additional floppy disks uses other names,
like "Extras" and "Fonts". Commodore
did not try to use the term "Workbench" as a broader
operating system brand.
Amiga Forever uses the word Workbench™ when referring to the
"Classic" operating system environment that runs on top of the
hardware.
Kickstart
The first Amiga, i.e. the Amiga 1000, had an additional floppy
disk, named "Kickstart". The Kickstart disk was needed because
when the Amiga 1000 shipped, the ROM-based part of the operating
system was not stable enough, so the machine was manufactured with
only enough code to load the ROM from the Kickstart disk. After
that, the Amiga 1000, like other Amiga models (which had a "real"
ROM chip on their motherboard), could boot from a Workbench floppy
disk, or from hard disk. Interestingly enough, the Amiga 3000 had
a similar problem (i.e. the hardware was finished before the new
operating system was ready), so that early versions of it loaded
their operating system ROM code from a "kickstart" file (located
on hard disk).
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