Number Systems

• Natural numbers


  Counting objects involves using the numerical symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
• Integers


  Any positive or negative whole numbers
• Rational numbers


  Values that can be expressed as fractions or ratios, including integers and recurring decimals
• Irrational numbers


  Numbers that cannot be expressed exactly as a fraction, with decimal values that are endless
• Real numbers


  Numbers that are either rational or irrational, used for measurement
• Ordinal numbers


  Numbers used to describe the position in which values appear
• Hexadecimal


  Base 16 number system that uses 0-9 and A-F to represent values 0-15
• Hexadecimal


  Easier to read and remember than binary, quicker to write/type, less chance of errors, used for colours, MAC addresses, assembly languages and machine code, easy to convert to/from binary
• Whole, rational and real numbers are represented by N, Q and R and used for counting and measurement
• Ordinal numbers are used for position
• Decimal numbers are easy to understand but not easy to use in electronics