Concurrency vs Parallelism

Concurrency: dealing with multiple tasks at once

Example: trying to eat while having a conversation.

• It might be possible to do so, but you can't talk while chewing your food because you only have 1 mouth.

• Your mouth switch context so often between chewing and talking, you might think that you are doing both in parallel at the same time (but actually, no).

• In the context of software engineering, having 1 mouth in the example is the same as having only 1 thread.

• Doing tasks asynchronously (with a single thread) will help us to achieve concurrency.

Parallelism: doing multiple tasks at once

Example: eating while having a conversation, but you have 2 mouths.

• You have 2 mouths so you can eat and talk at the same time.

• If eating while having a conversation will make the it finish at 10 minutes, having 2 mouths will help you to finish it in 5 minutes.

• In the context of software engineering, having 2 mouths in the example is the same as having 2 threads with different cpu cores handling them.