Vermicelli is an Italian type of pasta made from flour, eggs, and a bit of salt, resulting in thin noodles. It originated in the 14th century in Italy. It is named vermicelli (lit. small worms) because it is as fine and thin as tiny worms that are sometimes found in cheese.
Originally, young country girls would make vermicelli in the summertime, drying the pasta in the sun to make it last longer, and they would make enough vermicelli to last the entire year. Vermicelli pasta is somewhat thicker than spaghetti, but in the United States, it is the other way around.