5. Mechanics of Writing

Numbers and Numerals

A number is a characteristic that describes a unit within a collection. A number is expressed by numerals (1, 2, 3, 4) or by words. Cardinal numbers use words such as "one, two, three," while ordinal numbers use words such as "first, second, third."

In computer documentation, you will most often use numerals when numbers are discussed in text.

Spelling Out Numbers

Spell out:

      three computers (a count)
      3 inches (a measurement)

      You can choose from hundreds of applications for your computer.

      3 million instructions per second

      Ten files are required.

      Print twelve 500,000-byte files.

Using Numerals

Use numerals for:

      The menu offers 11 options, but you will use only 4.

      0.15
      1.25

      6 pounds
      3.5-inch disk drive

      Part 4
      Chapter 6

Punctuating Numbers and Numerals

Numbers and numerals generally require the same punctuation as words. Punctuating numbers and numerals becomes troublesome, however, when they are compounded.

      Your file comprises 500,000 bytes.

      Print your 500,000-byte file.

      1028 6000

      10,000 600,000

Using Fractions

The usage of numerals for fractions depends upon the context. Sometimes spelling out the fraction or using decimals is the preferred form.

      1/2-inch tape drive

      half the users in the test

      8 1/2 inches

      8 1/2-inch width

      5.25-inch drive

      3.5-inch diskette

      1/2-inch tape drive

      ten 1/2-inch tape drives (10 tape drives for 1/2-inch tape)

      10 1/2-inch tape drive (tape drive for 10 1/2-inch tape)

      
      
      
      
(Continued...)