Byte of the 8080 and the 8086, used in early personal computers, could also perform a small number of operations on the four-bit pairs in a byte, such as the decimal-add-adjust (DAA) instruction. A four-bit quantity is often called a nibble, also "nybble", which is conveniently represented by a single hexadecimal digit. The term "octet" is used to unambiguously specify a size of eight bits. It is used extensively in protocol definitions. Historically, the term "octad" or "octade" was used to denote eight bits as well at least in Western Europe; however, this usage is no longer common. The exact origin
Interpreter (computing) has been tested and debugged under the interpreter it can be compiled and thus benefit from faster execution while other routines are being developed. Many interpreters do not execute the source code as it stands but convert it into some more compact internal form. Many BASIC interpreters replace keywords with single byte tokens which can be used to find the instruction in a jump table. A few interpreters, such as the PBASIC interpreter, achieve even higher levels of program compaction by using a bit-oriented rather than a byte-oriented program memory structure, where commands tokens occupy perhaps 5 bits, nominally "16-bit"