The 1900's were the twentieth century. Except the year 1900 specifically was still the nineteenth century; the twentieth century started in 1901 and ended at th

The 1900's were the twentieth century. Except the year 1900 specifically was still the nineteenth century; the twentieth century started in 1901 and ended at the end of 2000, much to the chagrin of all the chumps who celebrated the millennium a year early. You know what would make all this confusion go away? Zero-based indexing.