You may think of it at a keyboard shortcut that you use every day. However, you may not know that it was invented for a completely different reason than for the one you use it for.

Now, most of us didn't know of the existence of CTRL+ALT+DELETE until possibly the mid 90's and beyond. However the shortcut was invented back in the 80's! The inventor, David Bradley was working on a project for IBM to create a personal computer. Since many other companies were way ahead of IBM the pressure was on to create the system in a year (instead of 3-5 years) so they could get it on store shelves.

Bradley said the most time consuming thing about building the machines was the fact that they kept locking up. Every time you'd have to reboot it would have to perform memory checks. This lost valuable time and lots of money!

So, Bradley invented the CTRL+ALT+DELETE so he could reboot the system without having to go through the memory checks. He created the shortcut in all of about 5 minutes.

Now, we use it all the time. Who knew it was a valuable part of creating some of the first computers.

[Source]