I get the general idea, but a more deep explanation about how each of these can be accessed and where they appear under a player, etc.
Can someone thoroughly explain the differences between a character, player, and humanoid?
2 answers
The Player is an Instance that is created in game.Players. It represents the player (the client, I believe) and its where the player's LocalScripts, GUIs and client-related stuff is kept.
The character is the physical representation of the player's avatar. This is a model in the workspace which holds character scripts, such as the Animate or the Sound scripts. The character is what the player controls and what actually interacts with the virtual enviroment.
Humanoids are Instances that can be placed inside NPCs (and of course Characters) to give them humanoid traits. For example, an object with a Humanoid will have a name tag, as well as a health bar (if enabled). Humanoids can also be used to animate the Character/NPC, and they basically control the functions of a character or NPC or whatever you put them into to make those things look much more... "humanoid".
I'm not a roblox proffesional and I can't say what I wrote above is 100% accurate, but I'm 99(.9999)% sure it is. I you want more information about each, as Fragmentation123 said in his answer, you can go to the following website articles:
http://wiki.roblox.com/index.php?title=API:Class/Player
http://wiki.roblox.com/index.php?title=API:Class/Player/Character
Character: A character is a model which contains: Head,Torso,Right Arm,Left Arm,Right Leg,Left Leg and most importantly a Humanoid , it is found in the workspace, and it can be accessed with: game.Players.LocalPlayer.Character , for more information: Wiki/Character
Player: A playeris an Instance which appears when a user joins the game, it appears under the Players service, for more information: Wiki/Player
Humanoid: A humanoid is the "controller" for a character, it holds walkspeed jumppower health etc, for more information: Wiki/Humanoid
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3 comments
So is the player a parent of the humanoid and character?
Player is separate of the the Character. The Character is found in the Workspace. The Player is found in game.Players. The Humanoid is a parent of Character. Character = Player.Character ; Player = game.Players.PlayerName ; Humanoid = Character.Humanoid
^