The IDE controller (Integrated Drive Electronics) is the control unit for the hard disk or the drive. It is either build directly in the hard disk / the drive or is connected as a separate plug-in card via a bus system to the motherboard. Per IDE controller (with one channel), two IDE devices can be connected. In a EIDI (with two channels) even four IDE devices can be connected. An IDE controller supports 63 sectors, 16 magnetic heads, and 1024 cylinders.
The SATA controller (Serial ATA) has a very similar operation. It connects the hard drive or the drive to the motherboard and controls data transmission. However, the SATA controller operates considerably faster than the IDE controller and is mainly found in newer computers.