A .PAT file is a library format that stores one or multiple "patterns." Unlike a standard JPEG or PNG, which is a static image, a .PAT file is designed for tiling . When applied to a layer or a shape, the software automatically repeats the image horizontally and vertically without visible seams, creating a continuous texture regardless of the canvas size. The Advantages of Using .PAT Over Standard Images

In software like Photoshop, patterns are often applied as "Layer Styles." This allows the designer to scale, rotate, or change the opacity of the texture at any time without permanently altering the original artwork. Common Applications

High-quality .PAT textures are engineered to be "seamless." This means the edges of the image match perfectly, avoiding the "grid look" often seen when repeating standard photos.

It covers the technical definition, the benefits of the format, and how to use them.