A Vertical Blind is a window covering made for a specific purpose. Although you can probably find them on any type of window, the best functionality for them is on a sliding glass door. If you need an idea on what they look like, make sure to visit TPrime Blinds. Getting back on topic, a vertical blind has a horizontal track that runs across the opening. This track is stationary but in it are little carriers that hold panels or panes. These panes will twist and slide side to side at your command. This is what makes them so great for sliding glass doors. You can slide them all to one side and not worry about having to raise and lower them like you would a regular blind.