What is the meaning of MarketplaceService, Replicated Storage, etc?

I'll not say anything that in here, so let start anyways c:

MarketplaceService

MarketplaceService is simply a thing that selling game passes and gears. And the way to local MarketplaceService is like this:

local ms = game:GetService("MarketplaceService") -- note: ms is a short-form of marketplaceservice

ReplicatedStorage

This have nothing to say. The thing that special is they were able to run a ModuleScript! Sadly, it can't run a Script, or a LocalScript.

the way to local ReplicatedStorage:

local rs = game:GetService("ReplicatedStorage") -- this have no information here.

Do I miss anything? I'll glad to help! Comment the thing that you want to ask, and bye bye~~~~~