A flat fee, also referred to as a flat rate or a linear rate, refers to a pricing structure that charges a single fixed fee for a service, regardless of usage.[1] Less commonly, the term may refer to a rate that does not vary with usage or time of use.
Synchronous: interrupt occurs as a result of current process, otherwise asynchronous. User requested: interrupt occurs because of direct result by user task, otherwise coerced. Maskable: if desired the interrupt can be disabled by a user task, otherwise unmasked.
Direct Memory Access, or DMA, is an absolutely essential part of any modern computing architecture. DMA allows the CPU to offload intensive memory access tasks to other components. This then frees the CPU from these menial chores and provides more cycles to more complex tasks for which it is better suited.