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.
Price. If your goal is to book the cheapest flight possible, book early. Look for a ticket at least three weeks in advance for the best price. Prices go up once you're 14 days or less away from the flight date. Smart Money recommends looking for online deals on a Tuesday or Wednesday.