These are not made of pixels.
Vector graphics (also called geometric modeling or object-oriented graphics) is the use of geometrical primitives such as points, lines, curves, and polygons, which are all based upon mathematical equations to represent images in computer graphics. Vector graphics is an alternative to raster graphics, which is the representation of images as a collection of pixels, as is typically used for the representation of photographic images.
Paths are vectors and not pixels and can be scaled up and down in size and transformed without loosing quality. There are numerous vector tutorials:
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