An Integrated Device Electronics (IDE) interface is used to connect Mass Storage media devices to the computer. These devices store large volumes of data. Some examples of this are Hard Disk, CDROM etc. This is the most common interface being used and is actually called ATA (Advanced Technology Attachment). IDE also refers to any device with the controller built-in.
Most of the disks today are IDE and these disks have built in controller. They can be plugged into a bus connector on the motherboard or an adapter card. Due to the fact that the controller is on the drive itself, these disks are easy to install and require a minimum number of cables. The short signal pathways improve reliability of the disks.
In the actual sense, ATA IDE is a much broader term than what we usually use. Most of the time, this is being referred to, just because this is the most popular interface. There are other types, like MCA IDE and XT IDE.
