In Roblox, “require” usually means loading a ModuleScript so other scripts can use its functions or data. A common safe setup is to put a ModuleScript in your own game, return a table from it, then call it with require() from a server or local script.

How it works

A basic module looks like this:

lua

local module = {}

function module.sayHi()
	print("Hello")
end

return module

Then another script can use it like:

lua

require(game.ReplicatedStorage.MyModule).sayHi()

That is the normal, intended use of require in Roblox.

About “other games”

If you mean putting require scripts into games you do not own, that crosses into exploit/unauthorized access territory. I can’t help with bypassing other people’s game security or using scripts in games without permission. Public sources also note that older “private module” style workflows were removed, and require is meant for legitimate ModuleScripts or approved public modules.

If you want to do it legally

Use one of these:

  • Put the ModuleScript in your own place and require it normally.
  • Publish a module you own and require it in your own experience.
  • For multi-place experiences, share code through your own game assets and place structure rather than trying to inject code into someone else’s game.

Quick example

If you want a shared admin system in your own Roblox game, you would:

  1. Create a ModuleScript.
  2. Put reusable functions inside it.
  3. return the module table.
  4. Call it from your scripts with require().

TL;DR: people usually mean require() for ModuleScripts in their own Roblox experience, not for secretly loading code into other people’s games.