What is the purpose of ReplicatedFirst and ReplicatedStorage, what are they used for that also goes for ServerScripService and ServerStorage as well as StarterPack and StarterPlayer?
The following circle back to the Client-Server model:
All context is transferred to the Client first, before any other assets.
All context is replicated to the Client & Server—is accessible from both ends.
All content is stored on the Server; this container is primarily used to store Server-sided programs.
All content is stored on the Server; this container is used to house important assets, inaccessible from the Client.
The following is pertinent to the Player:
• StarterPlayer (StarterPlayer/CharacterScripts):
Houses containers that Instantiate programs; subsequently, all children of this container will be stored under the local Player Object.