Are asynchronous and parallel programming the same?

In present days, async and parallel programming are spoken of interchangeably. But fundamentally, they both are a bit different. Asynchronous programming is used to enhance the usability of processes, while parallel programming aims for the computing/ processing efficiency.

Asynchronous programming

Async achieves parallelism by executing an independent piece of code separately from the rest of the process. Typically, asynchronous programs run on a single core and perform context switching. It executes in such a way that it does not block the flow of the process.

Syntax in C#:

Keyword Async tells the compiler that this function/ method contains await statement(s).

static async Task Main(string[] args)
{
    Coffee cup = PourCoffee();
    Console.WriteLine("coffee is ready");

    Egg eggs = await FryEggsAsync(2);
    Console.WriteLine("eggs are ready");

    Bacon bacon = await FryBaconAsync(3);
    Console.WriteLine("bacon is ready");
}

The await keyword does the magic and lets the next independent code execute rather than blocking them.

In the above code snippet, a call to the FryEggsAsync will not block the execution of FryBaconAsync.

Parallel programming

It is real parallelism. It means that you have multi-cores to run your application on. You write your application focusing on the maximum utilization of your CPUs. Each process runs on a separate core.