A noodle is a thin strip of pasta, usually cut or extruded from some kind of dough. It is the basic unit in dishes like spaghetti, linguine, soba, and udon. The term often refers to moist, cooked pasta, since it has connotations of curviness and slipperiness, but also to dried noodles that must be reconstituted by boiling or soaking in water. The word noodle derives from Latin nodus (knot), via German Nudel (noodle, pasta).

The big difference between noodle varieties is in the fat and water content. The instant or fried noodles contain only 3 to 6 g of water, compared to non-fried dried noodles, which have a water content of 12 to 14 g. The proportions are reversed for fat content - instant fried noodles have around 20 g, while non-fried dried noodles have as little as 3 to 5 g. Instant or fried noodles are subjected to an additional process step compared to dried noodles, they are deep fried in oil, hence part of the water is replaced by fat.