Exterior doors allow access, provide security and maintain a comfortable indoor climate. They're made to be particularly strong, weather-resistant and energy efficient. In addition, a front door is usually designed to project a handsome first impression.
A terrace or patio door is hinged and has glass lites. Hinged glass-lite doors mounted in pairs that swing independently are called French doors.
Exterior sliders have one fixed panel and one panel that glides along top and bottom tracks. Sliding doors operate easily, seal out the weather well and admit plenty of light.