Why Do Switches Use ‘I’ and ‘O’? The Power Button Explained [ID0703]
Why do almost all power switches use the same strange symbols? That tiny line and circle you see on electronics around the world aren’t letters, and they aren’t random.
In this video, we explore why switches use “I” and “O,” where these symbols came from, how they became an international standard, and why they’ve survived decades of technological change.
Timestamps:
0:03 – Intro
1:06 – What the “I” and “O” Actually Represent
2:03 – The Push for a Global Standard
3:02 – The Connection to Binary Thinking
3:58 – Why Symbols Outperform Words
4:49 – Related Power Symbols and Their Meanings
5:38 – Safety, Reliability, and Design Discipline
6:33 – Conclusion
#historyofsimplethings #power #symbols #technologyexplained #design #engineeringhistory #why #electronics #standards #iec #simplethingsexplained
Source
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