The Apple III was sold in two different configurations ranging in price from US,340 to ,800.
The Disk III floppy disk drives and an Apple Pro File 5 or 10 MB hard drive were available as options.
The Apple III project started in late 1978 under the management of Dr.
Wendell Sander, with the internal code-name Sara (named after Sander’s daughter).
The System Utilities program had three main sections: the Device handling commands section, the File handling commands section, and the System Configuration Program (SCP).The specifications were defined by a committee of Apple engineers to be implemented by Sander.Apple wanted the III completed in 10 months, but because of extra features constantly being added by the committee of engineers, it took two years. Many engineers began to feel like geniuses shortly after Apple’s initial public offering when their stock took off.The Pro File hard drive sat under the Monitor III in a typical setup (see photo), and required a special interface card, which plugged into an available slot on the Apple III.Internally, the Pro File used a Seagate ST-506 drive mechanism and a digital and analog circuit board designed and manufactured by Apple. The Pro File cost ,495 and was an important addition to the system, since IBM didn’t yet offer a hard drive for its PC.The additional benefit of SOS over older Apple DOS versions was the ability to use device drivers to support devices such as hard drives and RAM drives in addition to 5.25″ floppy drives.SOS also featured a built-in real-time clock and video capable of generating 24 lines of 80-column text and up to 560 by 192 pixels (in the monochrome graphics mode).The Apple III used its own operating system, SOS (Sophisticated Operating System), which was closed source and used a monolithic kernel.It influenced the design of the Pro DOS operating system, which was used on the Apple IIe and later Apple II series computers, and it also influenced the design of the Macintosh Hierarchical File System (HFS).Linzmayer in Steve Jobs, who supervised the project, didn’t help the situation.He gave the development team dimensions in which components would not fit and demanded the computer not have a cooling fan because they were “too noisy and inelegant”.