describe DMA

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@@ -160,6 +160,14 @@ Instructions: Please answer the following questions in complete sentences. Your
     this is typically handled in the hardware layer.
 
 1. Describe why direct memory access (DMA) is considered an efficient mechanism for performing I/O.
+
+    Reading data from different types of hardware can yield inconsistent I/O performance.
+    It can also degrage harder at a faster rate due to increased usage. DMA allows for
+    copying data from hardware into an in memory buffer that can be accessed directly.
+    This allows read sequential pieces of data from the hardware less often and speeds
+    up access to the data. One interrupt is generated per block rather than the one
+    interrupt per byte of data read.
+
 1. Describe why multicore processing is more efficient than placing each processor on its own chip.
 1. Describe the relationship between an API, the system-call interface, and the operating system.
 1. Describe some requirements and goals to consider when designing an operating system.