<P> Numeric keypads usually operate in two modes . When Num Lock is off, keys 8, 6, 2, and 4 act like arrow / navigation keys up, right, down, and left; and 7, 9, 3, and 1 act like Home, PgUp, PgDn, and End, respectively . When Num Lock is on, digit keys produce the corresponding digit . On Apple 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 . </P> <P> The arrangement of digits on numeric keypads with the 7 - 8 - 9 keys two rows above the 1 - 2 - 3 keys is derived from calculators and cash registers . It is notably different from the layout of telephone Touch - Tone keypads which have the 1 - 2 - 3 keys on top and 7 - 8 - 9 keys on the third row . </P> <P> 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 a calculator or adding machine . </P> <P> A numpad is also useful on Windows PCs for typing alt codes for special symbols, for example the degree symbol, °, with Alt + 0 1 7 6). </P>

What is the function of the numeric keypad
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