2.1. Definitions
A
digit is one of the characters used in any positional numbering system to represent all numbers starting at 0 and ending at one less than the base of the numbering system. In the decimal system, there are ten digits, 0 - 9, and in the hexadecimal system there are sixteen digits, 0 - 9 and a - f.
A
binary number system is one that uses only two digits, 0 and 1.
A
hexadecimal number system is one that uses sixteen digits, 0 - 9 and a - f.
CPU is an abbreviation for central processing unit. This is the "active" part of your computer, which executes all the
machine instructions that make the computer do useful work.
A
machine instruction is one of the fundamental operations that a
CPU can perform. Some examples of these operations are addition, subtraction, or other arithmetic operations; other possibilities include operations that control what instruction will be executed next. All C++ programs must be converted into machine instructions by a
compiler before they can be executed by the
CPU.
An
assembly language program is the human-readable representation of a set of
machine instructions; each assembly language statement corresponds to one machine instruction. By contrast, a C++ program consists of much higher-level operations which cannot be directly translated one-for-one into machine instructions.
