The Roman salute and the Nazi salute might look alike, but they have different origins and significance. Here's what we know about their differences.

The Roman salute is conditionally allowed in Italy and outright banned in Germany. German chancellor Olaf Scholz responded to Musk's gesture by saying, "We have the freedom of speech in Europe and in Germany," he said, "what we do not accept is if this is supporting extreme right positions."

The CEO of Tesla and SpaceX ignited controversy when he made an apparent Nazi salute during President Trump's second inauguration.