Drywall usually consists of a strong paper skin adhered to a gypsum core. The finish-ready face paper wraps around to the back of the panel at the sides, where it overlaps the coarser, more rigid paper used on the back.
For handling purposes, sheets of drywall are joined at the ends by removable strips of tape. To facilitate finishing, panels are typically tapered at the long edges. The shallow depression formed where panels meet is easily covered with tape and filled with joint compound for a flat surface that appears continuous.
The short, butt-end joints are not recessed and are more challenging to finish.
