The Explorer panel in Studio shows a list containing every Instance inside of a Place. This list uses the concept of parenting to organize all of the Instances hierarchically. If an Instance has any children, it will show an arrow next to its name in the Explorer. Clicking on this arrow toggles a list of all the children of that instance.
To make an Instance the child of another, drag it in the Explorer to the instance you want to be the parent.
To open the Explorer window, click on the View tab and then click the Explorer button.
Default Explorer organization
At the base level, the Explorer is organized into several categories and services.
|Workspace||Contains all of the visible objects in the Place. If you want Part or Model to appear in the game and be affected by the game's physics and other systems, it should be in here.|
|Players||Contains of the players currently in the Place.|
|Lighting||Controls various setting relating to lighting.|
|ReplicatedFirst||Replicates all of its contents to the player client before anything else is replicated. Useful for loading screens.|
|ReplicatedStorage||A storage service whose contents are accessible to the server and clients.|
|ServerScriptService||Stores and runs server-side Scripts in your place. Any active script inside this service will automatically run when the place starts. Contents are not replicated to clients.|
|ServerStorage||Stores instances on the server without replicating to the client.|
|StarterGui||Stores GUI elements which are replicated to a player's PlayerGui when the player joins the place or respawns.|
|StarterPack||Stores tools and scripts which are replicated to a player's backpack when the player joins the place or respawns.|
|StarterPlayer||Controls various player settings and LocalScripts that run when the player first joins the game.|
|SoundService||Controls various settings relating to audio.|