People have been using gold as a medium for finance for over two millennia. It has been a great way of representing money since is rare and you can not easily make a duplicate of the gold. Even now, the gold is used in many kinds of industry and consumer users. The most shocking thing is, about ninety five percent of earth’s total gold is deposited in the vaults as gold bullion. But if you are looking for an answer about why people buy gold; that will take some explanations.
Gold have less liquidity than any other medium of finance. Its value almost never decreases and you can easily convert it to other wealth. If your capital is converted to gold then after a decade it will be increased. It will not decrease. That is how gold is still in the top of the list, when you talk about safe investment.