How would you fire an event when a part touches another part?

I want an event to fire whenever a part touches another part. I've tried Instance.Touched for this, but that seems to only work when a player touches it. What should I do?

Hopefully this helps!

local part1 = game.Workspace.Part1
local part2 = game.Workspace.Part2 

part1.Touched:Connect(function(hit)
	if hit == part2 then 
		print ("Touched!")
	end
end)