The Post-it note, invente by 3M's Art Fry using an adhesive developed by a colleague, Spencer Silver, is a piece of stationery with a re-adherable strip of adhesive on the back, designed for temporarily attaching notes to documents and to other surfaces: walls, desks and table-tops, computer displays, and so forth. While now available in a wide range of colors, shapes, and sizes, the most common size of Post-it note is a 3-in (7.5-cm) square, canary yellow in color. The notes use a unique low-tack adhesive that enables Post-it notes to be easily attached and removed without leaving marks or residue. The name "Post-it" and the canary yellow color are trademarks of 3M. Accepted generic terms for competitors include "sticky notes" or "repositionable" or "repositional notes." 3M manufactures other products related to the Post-it note concept, leveraging the success of the brand. Computerized versions of Post-it notes include 3M's own "Post-it Software Notes." Until the 1990s, when the patent expired, Post-it notes were only produced in the 3M plant in Cynthiana, Kentucky. Although other companies now produce them, most of the world's Post-it notes are still made in Cynthiana.