Texture files
The terms "Texture" and "Sprite" often get confused in game development, so it's worth making the distinction that in Unity 3D a Texture is simply an image file; a big list of color data telling the interpreting program what color each pixel of the image should be. Whereas a Sprite is the 2D equivalent of a mesh, which just happens to be a single quad that renders flat against the current camera. There are also things called Sprite Sheets, which are large collections of individual images contained within a larger Texture file, commonly used to contain the animations of a 2D character. These files can be split apart by Unity's Sprite Batch tool, to form individual Textures for the animation frames.
Let's try to ignore all of these ...
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