The name spaghetti comes from the word “spago” (string). They are mentioned for the first time in a dictionary Giacinto Carena’s "Vocabolario Domestico" (1846) and then in the "Dizionario Tommaseo-Bellini" (1861-1879). The initial record of its use in English is by Eliza Acton in her Modern Cookery, dated 1849. It’s very hard to say who invented them. It’s absolutely untrue that Spaghetti were bought by Marco Polo (1254 – 1324) from China. In 1154, well before Marco Polo was born, the people of the Sicilian town of Trabia were making a form of pasta in long strands from hard, African-style wheat and exporting it all over Italy. Muhammad al-Idrisi, the court geographer to Roger II of Sicily, wrote it in the Book of Roger, the Tabula Rogeriana.
A spaghetto (singular) would have a round section with diameter between 1.9 and 2 mm and a length that averages 2.55 mm. Spaghetti have some brothers of different formats:
Spaghettini, with a diameter of ca 1.7 mm on average
Spaghettoni, with a diameter of ca 2.15 mm on average it is a real challenge to wrap them around the fork teeth
Vermicelli, with a diameter of approximately 2.07 mm on average
Vermicellini, similar in size to Spaghettini
Italians are often depicted as Spaghetti eaters and this fame was conquered after World War II when the annual consumption of spaghetti in Italy doubled from 14 kilograms per person before the war to the 28 kilograms of 1955. Italians still eat spaghetti but not in that massive quantities. The general consumption of pasta in Italy has dropped 23% in the last decade and Spaghetti likely followed the trend. However, by now pasta if the most consumed food in more than 50 countries around the world and spaghetti are the favourite format.
Spaghetti must be cooked always al dente, which means that they have to be firm but not hard. The term "al dente" means "to the tooth" or "to the bite" and refers to the need to chew the pasta due to its firmness. Spaghetti al dente has a lower glycemic index than pasta cooked soft.