# Introduction to placements

> Placeholder.

After you’ve developed your app, you can monetize and earn revenue from it by implementing different kinds of engaging mobile ads directly and strategically into it. Unity Ads provides the tools to serve a variety of engaging ad content to your app users through placements.

What a placement represents depends on how your app is set up.

## Placements for mediated apps

In a mediated app, a placement represents a bidding slot for a specific ad network, or a specific network within your mediation stack. You reference a placement ID when configuring Unity Ads as a bidder in a mediation platform like LevelPlay, MAX, AdMob, or another platform.

{/*
  ## Placements in non-mediated apps

  In a non-mediated app using Unity Ads, a placement represents a specific location in your game where ads are shown. For example, a rewarded video at the end of a game level or an interstitial between menu transitions.

  Placements are the main way to configure and expose ad inventory, and they no longer require a corresponding ad unit to be created first.

  Refer to [Create and manage a placement](/monetization/dashboard/placements/create-manage-placements) for instructions on how to create and manage placements in the Unity Monetization dashboard.

  ## Ad units for non-mediated apps

  Ad units were previously used to define ad inventory for apps using Unity Ads exclusively without a mediator. In the redesigned Monetization Dashboard, you can no longer create new ad units for non-mediated apps. However, any existing ad units you created previously continue to function exactly as before. Your ad delivery continues as usual, and no reconfiguration is required.
  */}

## How placements work

Placements use bidding to make ad requests, then select and serve the ad that achieves the highest eCPM (effective cost per mille), which is the average revenue your app earns from advertisers per thousand impressions.

These placements allow multiple ad networks and demand sources within a mediation tool to bid in real-time for the opportunity to show their ads in your app. This real-time competition among advertisers boosts your eCPM. Setting up bidding placements is straightforward and requires no manual target specifications.

You’ll need to create a placement in Unity Ads when you want to implement ads in any of the following ways:

* Monetize different parts of your app.
* Optimize ad delivery for specific user interactions.
* Optimize ad performance by running A/B tests.
* Control how and where ads are shown in your app.

Refer to [Create and manage a placement](/monetization/dashboard/placements/create-manage-placements.md) for more information.