Like the sibling says, octet is useful when in a networking context, because bytes weren't uniformly sized, but also because communications protocols were sometimes only 7-bit.
Serial ports and modems often operated in that mode, and UUCP influenced mail and newsgroups to only use 7-bit data; requiring encoding for data with the high bit set. Protocols that specify octets are dealing with 8-bit bytes and don't have to deal with that.
Serial ports and modems often operated in that mode, and UUCP influenced mail and newsgroups to only use 7-bit data; requiring encoding for data with the high bit set. Protocols that specify octets are dealing with 8-bit bytes and don't have to deal with that.