What metal is the best conductor of electricity?
That distinction goes to silver.
One way to assess conductivity, is to look up resistivity , which is a physical property of the substance that shows it tendency to resist the flow of electricity. The lowest resistivity among the metals is that of silver, followed by copper and then gold.
Gold, however, has the added advantage that it does not corrode, whereas silver and especially copper will do so. The corrosion will dramatically reduce their conductivity.
So, in electrical contacts, where exposure to air is present and corrosion can occur, gold is the ideal choice, despite a slightly higher resistivity. But, silver is still be best conductor overall.