# Overview

Shared Systems are features that are not tied to a specific feature but are integrated across multiple features.

The following Shared Systems features are available in LootLocker:

* [Metadata](https://docs.lootlocker.com/shared-systems/metadata): Metadata allows you to store additional, custom information in different formats.
* [Notifications](https://docs.lootlocker.com/shared-systems/notifications): Notifications track and communicate important player-related updates to the game.
* [Player Segments](https://docs.lootlocker.com/shared-systems/player-segments): Player Segments let you target certain systems to specific groups of players based on their behavior, activity, platform usage, or play history.