I was wondering that whether all the data in Computer has to go through the Processor or are there any Bypass Routes(like [DMA](https://en.wikipedia.org/wiki/Direct_memory_access)) through which data goes.

Consider following cases : 

1. **While downloading a file**: When downloading a file, does the data received by the Network Adapter goes directly to HDD(via RAM) or it has to be processed in Processor ?
2. **While opening a file**: For example, say I'm opening an audio file. So does the audio file needs to be processed by processor or it's data is directly relayed to audio devices?
3. **While playing a game**: Does the Graphics Processor directly access the RAM(or HDD) or it has to get the data & instructions from Central Processor(CPU)?

I'd like to know the route data takes when we do above actions.