While Integrated Drive Electronics (IDE) and Enhanced IDE (EIDE) both root themselves in the same concept of integrated electronics, only EIDE, as its name applies, has advanced standards. EIDE cables have 80 wires, for example, while IDE cables have 40, allowing EIDE channels to carry more information at the same time and transmit more signals to appropriate system-designated areas.
IDE first emerged as an idea in 1986, when Western Digital decided to implement hard-drive controller boards inside the drives themselves, as opposed to the previous method of placing the boards separately. Later, applications needed more speed and, in 1994, EIDE became a standard developed for faster transfer speeds and more-advanced drive setups.
Although EIDE and IDE use different cables, an EIDE cable can usually connect to an IDE connector and vice versa. Despite that reverse compatibility, you'll get the best performance out of your disk drives by using the proper cables for each standard. Note that some old IDE systems can't function properly with EIDE cables and drives. You might have better luck on a system manufactured after EIDE's release.
Standards like SATA and SCSI rose in favor of other methods of data transfer to meet newer system demands. Developed in 2003, SATA swept the drive market, nearly making IDE obsolete. Unfortunately, IDE hard drives can't connect in SATA ports because of the large physical differences. Interestingly enough, SATA implements a form of IDE, since the drive controllers still rest inside their respective drives, but the standard takes it in a direction that the original IDE controllers couldn't catch up with.
Clearly, IDE revolves around the concept of integrating a drive's controller board inside of it instead of separately. Although IDE may refer to any integrated drive electronics system, the term "IDE" often refers to the standard that appeared in 1986. All other standards that came after IDE applied its concept but called themselves other names to make the distinction in physical differences (particularly in the cables) and differences in performance.
The IDE concept sparked a new way of looking at drives and other devices when it was first introduced. Most standards employed as of 2010 contain controller boards inside the drives. SATA, for example, takes things a step further by reducing drive, controller cable and power-cable sizes. EIDE proves useful for advanced DVD and CD writers because of its speed, but the slower IDE standards can't catch up with the speeds of new drives.
- Photo Credit ide anschluss festplatte image by pmphoto from Fotolia.com ide connector on flat cable image by Sergey Galushko from Fotolia.com ide closeup image by .shock from Fotolia.com SATA connector. A close up. Isolated on a white background. image by Andrey Khritin from Fotolia.com