For postage stamps, separation is the means by which individual stamps are made easily detachable from each other. Methods of separation include: perforation - cutting rows and columns of small holes rouletting - small horizontal and vertical cuts diecutting - cut paper to shape using a metal die - used for self-adhesive stamps. Early years In the early years, from 1840 to the 1850s, all stamps were imperforate, and had to be cut from the sheet with scissors or knife. This was time-consumin… (More on Imperforate)