Rosh Hashanah is a two day holiday that marks the beginning of the new year. During this holiday, we eat special kinds of food at night and we blow the Shofar (Ram's horn). The Torah readings for Rosh Hashanah are from parashat Vayera which discusses the birth of Yitzchak as well as the Akeda, where Go-d asks Abraham to bring his son as a sacrifice. The Maftir on both days is from parashat Pinehas, the section that discusses the Holiday of Rosh Hashanah as well as the sacrifices that were offered in the Beit Hamikdash.