Historically, gold has the most proven track record as a currency, with civilizations spanning Northern Europe all the way to India using it as a medium of exchange.
However, the past century has seen governments completely abandon the gold standard and foist a fiat standard on their citizens, much to their economic detriment. As a result, unprecedented levels of inflation and government growth have been unleashed on millions of people worldwide.
Even with all of that government tampering in mind, people still turn to gold simply because it has such a proven record of being a hedge against inflation. Inflation puts everyday people’s savings in jeopardy, and holding gold at least preserves their wealth.
Whether or not there will be a return to a gold standard is a totally different story.
With the current ruling class we have, that's highly unlikely.