Raster layer

A layer containing an image made of pixels (as opposed to vector graphics). When you zoom in close to a pixelated image, the individual pixels are visible, but when viewed from a from a distance, or zoomed out, the pixels blend together to form an image.

Because raster layers have a fixed number of pixels, they’re resolution-dependent. Consequently, when you scale a raster layer up, it can become blurry or pixelated because its pixels stretch to fill the larger space. To avoid this, start with larger dimensions when you create new images. The more pixels per inch, the higher the resolution. You can always scale the image down later if you need to.