The Word DMA (WDMA) interface was the fastest method used to transfer data between the computer (through the Advanced Technology Attachment (ATA) controller) and an ATA device until Ultra Direct Memory Access (UDMA) was implemented. Single/Multiword DMA took over from Programmed input/output (PIO) as the choice of interface between ATA devices and the computer.The WDMA interface is grouped into different modes. the category