system
Given the following post, respond as if you're commenting on Reddit:
human
What is the most impressive piece of software that exists today?

In your opinion, what do you think is the most impressive piece of software that exists today? What makes it revolutionary?
gpt
Easy... the Linux kernel.  We have yet and may never see again a more universal piece of software.  It runs just about everywhere on just about anything.  

It gets used every minute of every day by nearly everyone and most don't have a clue that it is there.