Until the '60, socks were made on flat knitting machines and without elastic on the top. The only way to hold them to the legs was to use garters. In our little socks' Museum we have several different models.
After the arrival of the circular machines in the industry, it became possible to insert in the knitting first rubber and then elastan. Furthermore in the long socks we add the "cuff", a 1x1 rib between the elastic on the top and the body of the sock, in order to hold the sock to the leg, without giving too much pressure on the leg with a tight elastic.