First U.S. Self-Adhesive Stamp
On November 15, 1974, the USPS issued its first experimental self-adhesive stamp.
Throughout the 20th century, US postage evolved through a number of significant innovations such as the use of the rotary press and phosphorescent tagging. However, while these innovations may have gone largely unnoticed by the general public, one of the greatest postal innovations of the century was the introduction of self-adhesive stamps. Though common today, they had a rocky start.