What is IRQ 14 used by?

IRQ 14 is primarily used by the Advanced Technology Attachment (ATA) interface, specifically for the primary IDE (Integrated Drive Electronics) hard drive. It allows the operating system to communicate with hard drives connected via the IDE interface, managing data transfer and device control. In modern systems, however, IRQs are often managed by the operating system, and the traditional usage of IRQs has diminished with the adoption of technologies like SATA and USB.