Multiple Roblox refers to the ability to run multiple instances of the Roblox game client simultaneously on a single computer. Here are a couple of ways you can achieve this:

1. Third-Party Programs:

   • You can use third-party programs like MultiRoblox, which is an open-source tool that allows you to open multiple instances of Roblox. It provides a way to run separate Roblox sessions side by side. 
   • Another option is to use an app called “Multiple Games”, which lets you log in and out of different Roblox accounts while keeping other accounts running. This way, you can have as many instances of Roblox running as your CPU allows ².

2. Built-in Roblox Features:

   • Roblox itself allows you to use multiple accounts on one PC:
     • Open the Microsoft Store and search for Roblox.
     • Launch the Roblox application.
     • Add an alternate account by navigating to the Friends section and searching for your alt account. Make sure to add that account.
     • Accept the friend request with your alt account.
     • Now you can join Roblox experiences with your second account ³.