"History is a gallery of pictures in which there are few originals and many copies" - Alexis de Tocqueville.

It’s been a long time since the days of command-line interfaces, where we accomplished the vast majority of tasks with a keyboard, and the use of a mouse was rare or unknown.

But even though we’re all used to pointing and clicking these days, plenty of keyboard shortcuts are still incredibly useful. But did you ever take a moment to think about where some of these seemingly random combos actually came from?

In today’s IT Guidelines & Tips, we’re going to take a look at a bit of the history behind them, starting with our old friend CTRL+ALT+DEL.

The engineers behind the original IBM PC in the early 1980s wanted a quick way to restart the machine from the keyboard. But they didn’t want to make it too easy, lest the user accidentally reboots the computer and lose whatever they were working on. At first, CTRL+ALT+ESC was proposed, but all three of those keys are on the same side of the keyboard. So, it was thought that combination would still be too easy to trigger by mistake. So instead, DEL was assigned to be the third key.

Funnily enough, even though CTRL+ALT+DEL persists as a standard key shortcut to this day, it was originally intended just for development use but was leaked to the public after it was included in some IBM reference documents.

By the time Windows 3.0 rolled around in 1990, the combination was no longer linked to the BIOS as a way to reboot the computer immediately. Instead, the OS presented you with a screen, allowing you to go back, terminate the program that was running, or reboots the whole system by pressing the combination again, and Windows 95/98 gave us a similar screen that allowed us to close any running program. In Windows XP, the combo would bring up the Task Manager instead, and nowadays Windows 10 gives us a screen with several useful options when pressing CTRL+ALT+DEL, but pressing the keys again actually doesn’t do anything

Let’s move on to another one we use quite a bit, ATL+F4, for closing a program or a window. When you think about it, it seems pretty random. Why not something like ALT+C for close or ALT+G for just go away?

Well, ALT+F4 has its origins in a 1987 IBM project called Common User Access. The idea was to standardize how a user would interact with software, no matter what kind of system or program they were using as back then, different programs had wildly different key combinations to accomplish the same task, even among the same class of application, such as word processors. Some of the standards are still in use today, such as F5 to refresh a page. The reason ALT+F4 was mapped to the close function was that the designers used other ALT+FN key combinations to manipulate Windows in different ways, such as ALT+F8 to resize and ALT+F10 to maximize.

And although many of these shortcuts have fallen by the wayside because people weren’t using them, ALT+F4 remained popular. So, it still serves as a quick way to close your browser if your boss walks in and you don’t want him/her to know you were doing something other than working.

Speaking of hiding whatever it is you were doing, let’s finish up by talking about ALT+LEFT-ARROW. If you’re a fan of using keyboard shortcuts specifically in your web browser, you might be familiar with this one. It’s the way to go back one page without clicking the mouse, but going back is something we do super frequently. So why not just have one button for it instead of a combination? Well, we actually used to.

It wasn’t too long ago that you could actually hit BACKSPACE to go back a page in many web browsers. But a big problem was that people kept hitting the key by mistake. Users would be filling out the form on a webpage, and need to delete something, but accidentally click outside of the textbox, meaning the BACKSPACE button would take them off the page rather than just delete one character. And oftentimes when the user would click forward to get back on the intended page, they discovered all the data they’d entered was wiped out. This led Google to change the shortcut in Chrome in 2016, which is now standard across major web browsers.