What is vCharacter and waitforChild(Parent, instance)?

Another Question :D I have someone who is VERY generous and told me to get this Free Model and look at the scripts, and I did, and I came across two things, 'Vcharacter' which made no sense, the Parent of the script, which is the Tool itself, is not represented in that matter in the script, take a look

local vCharacter = script.Parent 
local vTorso = waitForChild(vCharacter, "Torso")
local vHumanoid = waitForChild(vCharacter, "Humanoid")

I do, know what 'WaitForChild' is. And also this,

local function waitForChild(parent, instance)
    while parent:FindFirstChild(instance) == nil do 
        wait()
    end 
    return parent[instance]
end

What is this? >:l