All the above is true depending on which state the plates were issued.
In California for example: New steel plates were stamped and issued every year through the 1940s. In the early 1950s, black/yellow steel plates were issued to run several years and colored metal registration tags were affixed by screws for each year up through 1955. In 1956, stamped steel yellow/black plates were issued and colored registration stickers were updated each year. This plate and sticker method continues through the present, with a new plate series issued every few years and personal vanity plates also available. Plates are now made from stamped aluminum. And since 2018, digital plates can also be obtained from CA DMV.
