<P> The latest generation of user - generated airline seatmaps include comments from frequent flyers, and one specialised website has gained access from airlines to take pictures of every seat, and sit in them to write specific recommendations, alongside the detailed seat maps . </P> <P> On many aircraft, the rightmost seats have letter designations HJK, skipping the letter I . This is because each seat has a row number followed by letter . Letters that confuse with numbers must be avoided . Digital Equipment Corporation (DEC) was the first to implement this, avoiding I (1), O (0) and S (5). The remaining letters are called the DEC alphabet . </P> <P> Occasionally, aircraft with a seating structure of 2 + 2 may letter the seats as "ACDF" to keep with the standard of A / F being window and C / D being aisle on short - haul aircraft (which generally have 3 + 3 seats). </P> <P> In First and Business class cabins, the seat letters for the window seats will typically be the same as in coach, with some letters skipped in between as there are fewer seats per row . For example, if economy cabin is ten across, labeled ABC - DEFG - HJK, the Business Class cabin might be labeled AC - DG - HK for a six across layout, with A-DG - K for a four across First Class . One notable exception to this is Delta Air Lines, who uses sequential letters regardless of cabin layout on all aircraft (AB - CD - EF in Business Class and ABC - DEF - GHJ in Economy). </P>

Is a the window seat on a plane