United Airlines has opened CLEAR lanes at Chicago O'Hare International Airport's Terminal 1. New checkpoints will become available in Terminal 2 in the next few weeks. The addition of the CLEAR service has been perfectly timed with the busy holiday travel season.

CLEAR is a paid-for service that allows people to verify their identity through biometrics. CLEAR members can scan their fingerprint or iris to have their identity confirmed simply with a 'blink of an eye' or 'touch of a finger'. Thereafter, they can continue on to physical screening.

The location of the CLEAR lines is very convenient for United Airlines travelers, though passengers of any airline can use these lines when going through security. The CLEAR lanes are available from 4am to 8pm.

Over 4 million people have already become CLEAR members. Each of these clients can seamlessly access over 60 different venues that require identity confirmation, including over 30 airports across the country.

CLEAR membership costs $179 per year. United Airlines offers free membership to Premier 1K and Global Service Elite members. Mileage Plus members can enjoy a discounted membership price. United US credit cardholders also enjoy a discounted membership fee. Earlier this month, United Airlines launched CLEAR at Houston Airport.

The CLEAR process helps make security checkpoints more manageable. The holiday travel season can make getting through security much harder because of the volume of flights taking place at every airport. United Airlines is more than happy that the CLEAR system has been launched in time for the busy season so its customers can look forward to enjoying a more pleasant travel experience this season.

Delta also offers free and discounted memberships to their customers. Discounted memberships are available for students, too.

Adam Luehrs is a contributing writer at GET.com based in California. He likes traveling to new and exciting destinations, preferably on his credit card company's dime. When not on the road, Adam enjoys hiking around the mountains of San Diego, trying out new food and reading history books. Email: adam.luehrs@get.com.