<i>"[...] Ctrl+Alt+Del because it was impossible to press with just one hand."</i><p>At first I thought, <i>"Well, not impossible, really..."</i>, because you can "play the chord" with your right hand:<p>Pointer (Ctrl) + Thumb (Alt) + Middle (Delete)<p>But...<p>The older keyboards [1] only had a single "Ctrl" key and a single "Alt" key. They were located on the left side of the keyboard, while the single "Del" key was located on the right side.<p>So, with that configuration, it actually was impossible to perform the combination with a single hand.<p>[1] <a href="https://www.google.com/search?q=%22IBM+5150+Keyboard%22&tbm=isch" rel="nofollow">https://www.google.com/search?q=%22IBM+5150+Keyboard%22&tbm=...</a>