Libs - it is common functionality. You can use it for any your tasks.
For example Bots.Business have such Libs:
Random Lib - for random messages from bot
Referral Lib - for referral tracking
ResourcesLib - for chat resources with growth and etc
Lang Lib - for multi language
1.Go to Libs Tab in the App
2. Click on Install button
3. Select your bot
Please see help article for this Lib.