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.
It really varies. Typically flight prices go up the closer to the flight date. But if it's close to the flight date and there are still seats available, then prices might go down during a seat sale in a final attempt to sell out the flight. I find it's really hard to predict flight prices. In most cases, I book as early as possible, and have always got the best price doing it that way.