Stall boarding is a method of loading passengers onto an aircraft where they board in small groups based on their seat assignments. This process helps to reduce congestion in the aisles and allows for a more organized boarding experience. Passengers are typically called to board by rows, starting from the back of the plane to the front, or by specific zones. This boarding technique contrasts with traditional methods, such as general boarding, where all passengers are allowed to board at once. Airlines like Southwest Airlines often use stall boarding to improve efficiency and minimize delays during the boarding process.