Double-click on the Sprites folder. Once inside, go to your operating system's browser window, open up the Chapter 1/Assets folder that we provided, and drag the playerShip.png file into the folder to move it into our project. Once added, confirm that the image is Sprite by clicking on it and confirming from the Inspector tab that Texture Type is Sprite (Sprite (2D and UI) in 4.6). If it isn't, simply change it to that, and then click on the Apply button. Have a look at the following screenshot:

Next, drag-and-drop the ship into the Scene tab (the center part that's currently dark gray). Once completed, set the position of the sprite to the center of the Screen (0, 0) by right-clicking on the Transform component and then selecting Reset Position. Have a look at the following screenshot:

Now, with the player in the world, let's add in a background. Drag-and-drop the background.png file into your Sprites folder. After that, drag-and-drop a copy into the scene.

If you put the background on top of the ship, you'll notice that currently the background is in front of the player (Unity puts newly added objects on top of previously created ones if their position on the Z axis is the same; this is commonly referred to as the z-order), so let's fix that.

Select your background object, and go to the Sprite Renderer component from the Inspector tab. Under Sorting Layer, select Add Sorting Layer. After that, click on the + icon for Sorting Layers, and then give Layer 1 a name, Background. Now, create a sorting layer for Foreground and GUI. Have a look at the following screenshot:

Now, place the player ship on the foreground and the background by selecting the object once again and then setting the Sorting Layer property via the drop-down menu. Now, if you play the game, you'll see that the ship is in front of the background, as follows:

At this point, we can just duplicate our background a number of times to create our full background by selecting the object in the Hierarchy, but that is tedious and time-consuming. Instead, we can create all the duplicates by either using code or creating a tileable texture. For our purposes, we'll just create a texture.

Delete the background sprite by left-clicking on the background object in the Hierarchy tab on the left-hand side and then pressing the Delete key. Then select the background sprite in the Project tab, change Texture Type in the Inspector tab to Texture, and click on Apply.

Now let's create a 3D cube by selecting Game Object | Create Other | Cube from the top toolbar. Change the object's name from Cube to Background. In the Transform component, change the Position to (0, 0, 1) and the Scale to (100, 100, 1).

Since our camera is at 0, 0, -10 and the player is at 0, 0, 0, putting the object at position 0, 0, 1 will put it behind all of our sprites. By creating a 3D object and scaling it, we are making it really large, much larger than the player's monitor. If we scaled a sprite, it would be one really large image with pixelation, which would look really bad. By using a 3D object, the texture that is applied to the faces of the 3D object is repeated, and since the image is tileable, it looks like one big continuous image.

Remove Box Collider by right-clicking on it and selecting Remove Component.

Next, we will need to create a material for our background to use. To do so, under the Project tab, select Create | Material, and name the material as BackgroundMaterial. Under the Shader property, click on the drop-down menu, and select Unlit | Texture. Click on the Texture box on the right-hand side, and select the background texture. Once completed, set the Tiling property's x and y to 25. Have a look at the following screenshot:

Finally, go back to the Background object in Hierarchy. Under the Mesh Renderer component, open up Materials by left-clicking on the arrow, and change Element 0 to our BackgroundMaterial material. Consider the following screenshot: