You can readily identify an e-Passport, because it has a unique international symbol on the cover. Electronic System for Travel Authorization (ESTA) ESTA is an automated system that determines the eligibility of visitors to travel to the United States under the Visa Waiver Program (VWP). Authorization via ESTA does not determine whether a traveler is admissible to the United States.
Two to three weeks before the flight date, the price quotes start increasing. This is the time when business travelers start booking. While price drops are still possible, a chance of a price increase is much higher if you wait to book within this time period.
The online airfare shopping engine tracked prices from 320 days in advance up until the day before a flight and found the prime booking window was generally one to four months ahead of departure. The lowest price of a ticket changed around 70 times when it was for sale, the report found. By booking on the cheapest day, fliers saved an average of $201 on airfare, excluding the 14 days before a flight since fares are much higher then. If those two weeks are included, the difference rises to $319.