There are a few different types of pocket doors.
Solid pocket doors are the most common type of pocket door. Solid pocket doors are fitted for a standard 36-inch-wide opening, and are essentially solid panels that match this width and slide on a track into the wall. You’ll likely find solid pocket doors in standard small rooms that would benefit from a space-saving opening.
When it comes to double doors, it’s right there in the name. They are pocket doors with a door on each side that come together. Double pocket doors are best for wider entryways, like those that may lead into a dining room. Because double pocket doors require two pockets—one on each side— it’s best to install these where there is plenty of free wall space on each side.
French pocket doors are, in a sense, a combination of both double doors and solid doors. Like double doors, they have two doors and require two wall pockets, but rather than being used in wider entryways, they are suited for the standard 36-inch wide opening. French doors can be installed with solid panels but are most commonly designed with glass panes.