“Heard a few people say it is the current that kills, not the voltage. I have to disagree.” An awesome and flawless explanation in this video.
What is interesting to me is how the AC power standards for Europe and US developed. There are pros and cons of each system.
The US System is based on 120V @ 60Hz
The European system is 220V @ 50Hz
American plugs are smaller and easier to handle. Some plugs have three prongs (ground) and one larger blade. The larger blade on a two prong plug often causes problem during insertion. The main advantage of the US system is the reduced threat of accidental electrocution as compared to 220V standards.
The British three prong plug is unique within Europe. It’s a smart plug in that the ground lug forces open the shields to the hot wires. There’s no mistaking how it inserts. The plugs are often fused and the wall panels are often switched. This is a seriously safe and feature robust plug, however, it’s also a very large bulky plug. The downside, as stated above, is the increased risk of fatal electrocution.
Another advantage of the European standard is the reduced amperage, which in turn requires less copper (heavy gauge wire).
Most electronics are switched thus will work on either standard, except for hair dryers and shavers or devices with heated elements. For those items a transformer is needed.