The Apple IIe is arguably the most successful computer Apple has ever produced. The IIe was introduced on January 1983 originally selling for $1395, and included the same 1.02 MHz 6502 processor as the Apple I and II. The Apple IIe included the new ProDOS operating system designed from the ill-fated Apple III's SOS, and Applesoft BASIC burned into the 32k ROM. The IIe contained 64k RAM built-in, and allowed up to 128k RAM using the 80 column card which allowed 80 column text and an additional 64k RAM (much more RAM could be added later via third party hardware). The IIe also allowed upper and lower case letters be used allowing full functionality of the Shift and Caps Lock keys. The main goal of the IIe was succeed where the Apple III had failed, create a professional computer for use in business. It served its purpose well, and also became abundant in schools and homes. The next of several versions of the IIe was one with a sharper display (560x192 black and white, 140x192 in 16 colors). In March 1985 came the IIe enhanced, which was basically upgrading a IIe to IIc standards, including a new 65C02 processor, character generator, new ROM, and 2 more ROM chips for Applesoft BASIC and the monitor. In 1987, the final major revision, the IIe extended, was released. The IIe extended most noticeably added a numeric keypad to the built-in platinum keyboard. Other new features included a miniaturized 80 column card and several internal memory enhancements. Due to the fact that the IIe could be upgraded to a IIc or a IIGS and more compatible with original Apple II software than even the Apple II compatible clones, the bulk of Apple II software (95%) works on an enhanced IIe might explain why it was such a favorite among businesses, schools, and home computer users. All models were discontinued in November 1993 for a combine total of almost 11 years on Apple's production line, outliving every other model including the IIGS, discontinued the year before.

Code Names: Diana, LCA (Low Cost Apple).

Specifications:
Processor: 6502 processor running at 1.023 MHz (same as Apple I and II), later IIe's used a 65C02 processor. Memory: came with 64k of RAM expandable to 128k using 80 column card, or several MB using a third party expansion slot.
Display: was allowed 80 column text of upper and lower case letters, and up to 560x192 resolution in black and white and 140x192 in 16 colors.

Operating Systems:
ProDOS: all versions (ProDOS made its debut with the IIe).

Models in this Series:
IIe: basic system, 64k RAM, 6502 processor, 40 column screen.
IIe enhanced: 65C02 processor, 128k RAM, 80 column screen.
IIe extended: extended keyboard, new internal memory chips (shown left).

On the market for: 1 year, 3 months (IIe); 8 years, 9 months (IIe enhanced).

Interesting Facts:
The IIe probably went through more changes of its original name than any other Apple computer. In 1983 it was the Apple ][e. From 1984 to 1986 it was the Apple IIe, and from 1986 to it's discontinuation in 1993 it was the Apple IIe. You may have noticed that I only use the "I" for all models. I thought a lot about using their original names but decided it would be too inconsistent and used only "I" and not "]" nor "/".

Resources and Related Links:
The Apple IIe entry at Glen Sanford's A History of Apple Computer
The Apple IIe entry at Richard Kilpatrick's Apple Retro
The Apple II FAQ from comp.sys.apple2
Both pictures from A History of Apple Computer