Octet
An octet is a word used to describe the sequence of 8 things in a row.
In music, an octet is an ensemble consisting of eight instruments or voices, or a composition written for such an ensemble.
Technology
Octets are used in the technology field very often. For example, the eight binary digits in a byte has been called an octet. The term "octet" is used to avoid ambiguity, because some old computers had different numbers of bits per byte. It is mainly used with describing IP addresses. An IPv4 address consists of four octets (which can be written as their decimal values 255.255.255.255).
In France, French Canada and Romania, "octet" is used in common language instead of "byte" to talk about 8 bits, for example, a megabyte (MB) is called a megaoctet (Mo).
Numbers