For volume shippers looking for the most economical ground delivery, Parcel Select is the best option available. As of January 27, 2013, Parcel Select was split into Parcel Select, for online purchasing, and Standard Post for purchasing at the Post Office. Parcel Select is significantly cheaper than Standard Post.
Pocket door. A pocket door is a sliding door that disappears, when fully open, into a compartment in the adjacent wall. Pocket doors are used for architectural effect, or when there is no room for the swing of a hinged door. They usually travel on rollers suspended from an overhead track, although some also feature tracks or guides along the floor.
RON HAZELTON: Now this is called a pocket door. It's actually a sliding door that goes up inside the wall, and these have some real advantages. For one thing, they don't require room to swing, and when they're completely open, they're completely out of sight.