A flight booking service allows travelers to search, compare, and reserve airline tickets online or through an agent. It offers convenience, real-time availability, price comparisons, and options for different airlines, classes, and routes—all in one place. Many services also include features like flexible date searches, seat selection, and customer support.

"OK to Board" is a verification service required by some Gulf countries for travelers with certain nationalities (e.g., India, Pakistan, Bangladesh). After booking a flight and getting a visa, the airline rechecks the visa and travel documents before allowing boarding. Once verified, the airline updates the passenger's PNR with an "OK to Board" status. Without this, boarding may be denied.