Normale, in the context of espresso, is the standard way of extracting a shot. A single shot normale is obtained by extracting approximately 1 oz of coffee, using 7 grams of ground coffee. A single is often named solo, using the Italian word for it. A normale is the standard espresso concentration, whereas ristretto is a concentrated version, and lungo is the diluted version of it.
An espresso normale can be pulled into a doppio, (a double shot), or a triplo, (triple shot), by using different size filter baskets.