How come this script can attack whoever closet to it? can someone explain

local myHuman = script.Parent:WaitForChild("Humanoid")
local myRoot = script.Parent:WaitForChild("HumanoidRootPart")

local attackCool = true
local clone = script.Parent:Clone()





function checkDist(target)
	return (myRoot.Position - target.Position).Magnitude
end

function getUnstuck()
	myHuman:Move(Vector3.new(math.random(-1,1),0,math.random(-1,1)))
	myHuman.Jump = true
	wait(0.5)
end



function findTarget()
	print("Hello")
	local dist = 50
	local target = nil
	for i,v in ipairs(workspace:GetChildren()) do
		local human = v:FindFirstChild("Humanoid")
		local torso = v:FindFirstChild("Torso") or v:FindFirstChild("HumanoidRootPart")
		if human and torso and v.Name ~= script.Parent.Name then
			if checkDist(torso) < dist and human.Health > 0 then
				target = torso
				dist = checkDist(torso)
				
			end
		end
	end
	return target
end




function attack(target)
	if attackCool == true then
		attackCool = false
		
		
		
		target.Parent.Humanoid:TakeDamage(10)
		
		spawn(function() wait(0.5) attackCool = true end)
	end
end



function main()
	local target = findTarget()
	if target then
		if checkDist(target) > 6000 then
			getUnstuck()
		else
			attack(target)
		end
	else
		getUnstuck()
	end
end

while wait() do
	if myHuman.Health > 0 then
		main()
	else
		break
	end
end







function attack(target)
	if attackCool == true then
		attackCool = false
		
		
		
		target.Parent.Humanoid:TakeDamage(100)
		
		spawn(function() wait(0.5) attackCool = true end)
	end
end