What does (h)=?

So here I have a script and I do not understand what (h) is connected to. So please explain what (h) is to me.

function tch(h)
if (h.Parent.Name == "Drink1") then
h.Parent.Name = "HamDink"   --Edit this to the name of the drink
h.Parent.Transparency = 0.1 -- change this to the transparency
script.Parent.Parent.Spill.Transparency = 0.1
wait(0.5)
script.Parent.Parent.Spill.Transparency = 1 --no touchy
end
end

script.Parent.Touched:connect(tch)