Seat arrangements on a Boeing 777 vary by airline. Each airline typically has some variation of first-class, business-class, economy-plus and economy-class seats. For example, Delta Airlines Boeing 777-200ER/LR contains 37 "Delta One" first-class seats, 36 "Delta Comfort Plus" seats and 218 economy seats. The economy seats are in three sets of three seats. The grouping of seats also varies by airline. Higher-class seats are always toward the front of the plane.
American Airlines Boeing 777-200 (777) V1 uses equal parts of its floor space for first- and business-class seating and economy-class seating. There are 16 first-class seats, 37 business-class seats and 194 economy-class seats. The economy-class seats are grouped as two-five-two, with aisles separating the groups.
United Airlines Boeing 777-200 (772) V3 provides more space for economy-class by combining first- and business-class seats. The plane contains 50 "BusinessFirst" seats, 72 economy-plus seats and 145 economy seats. The economy seats are separated into three groups of three seats.
An overview of nearly any flight's seating arrangement is viewable when ordering tickets online. Many airlines allow the buyer to select a seat at the time of purchase. Some airlines, however, do not allow the buyer to select a seat until tickets are distributed at the airport, and others do not allow seat selection at all.