A numeric keypad, or numpad for short, is the small, palm-sized, seventeen key section of a computer keyboard, usually on the very far right. The numeric keypad features digits 0 to 9, addition (+), subtraction (-), multiplication (*) and division (/) symbols, a decimal point (.) and Num Lock and Enter keys. Laptop keyboards often do not have a numpad, but may provide numpad input by holding a modifier key (typically labelled "Fn") and operating keys on the standard keyboard. Particularly large laptops (typically those with a 17 inch screen or larger) may have space for a real numpad, and many companies sell separate numpads which connect to the host laptop by a USB connection.It also provides a calculator-style keyboard for efficient entering of numbers.
Numeric keypads usually operate in two modes: when Num Lock is off, keys 8, 6, 2, 4 act like an arrow keys and 7, 9, 3, 1 act like Home, PgUp, PgDn and End; when Num Lock is on, digits keys produce corresponding digits. These, however, differ from the numeric keys at the top of the keyboard in that, when combined with the Alt key on a PC, they are used to enter characters which may not be otherwise available: for example, Alt-0169 produces the copyright symbol. These are referred to as Alt codes. On Apple Computer Macintosh computers, which lack a Num Lock key, the numeric keypad always produces only numbers. The num lock key is replaced by the clear key.
The arrangement of digits on numeric keypads is different from that of telephone “Touch-Tone” keypads—this may be confusing for those who use one of these arrangements more often. However, the arrangement of the numbers is similar to that on the keyboards of calculators.
Numeric keypads are useful for entering long sequences of numbers quickly, for example in spreadsheets, financial/accounting programs, and calculators. Input in this style is similar to that of a calculator or adding machine.
Numeric keypads are also useful for playing some computer games where the player must control a character, for example roguelikes. Unlike arrow keys, the numeric keypad allows diagonal movement. For keyboards without a numeric keypad, some games provide alternative movement keys, such as classic Rogue's HJKL keys.