Ethernet, Token Ring, and FDDI hardware addresses are 48 bits (6 octets), expressed as 12 hexadecimal digits. These 12 hex digits consist of the first, leftmost 6 digits that match the vendor of the interface within the station, and the last, rightmost 6 digits which specify the interface serial number for that interface vendor. These addresses can be written in a number of ways. For example, the addresses might be written unhyphenated (e.g., 123456789ABC), with one hyphen (e.g., 123456789ABC), with colons between each octet (e.g., 12:34:56:78:9A:BC). Most people however write addresses hyphenated by octets (e.g., 12-34-56-78-9A-BC), and this has now become the accepted form.