Numbers
Numbers followed by units of measure should never be written out. - Bad: It was a one GB hard drive
- Good: It was a 1 GB hard drive
Single digit numbers ( zero through nine) should usually be written out. - Example: There were nine cables.
References to numbers as they appear in text should be in quotes, or bold, and should match the way they are represented in that text. - Example: There were nine cables numbered "1" through "9".
- Example: Go to the menu and select ten or more.
Numbers that start a sentence should be written out - Example: Thirteen revisions have been created.
Single digits compared with multiple digits do not need to be written out: - Example: Approximately 1 in 300 modems failed in the first year.
Numbers enumerating nouns that are defined by a number should be written out. - Example: There were twenty-seven 802.11 abg wireless pc cards in stock.
Units of measurements
Abbreviations of units should not be followed by a period unless they are at the end of a sentence. Abbreviations of units should be lower case except in the following situations: Units of measure named for a person should be upper case (e.g.: kHz). Bytes are abbreviated B, bits b (e.g.: 5 GB hard drive and 1Gb Ethernet. Metric abbreviations are case-sensitive, so uppercase and lowercase letters have different meanings - mm stands for millimeter (one-thousandth of a meter)
- Mm stands for megameter (one million meters)
The plural of the abbreviation of unit of measure is the same as the singular (i.e.: never add an "s") Units of computer memory
The computer industry commonly refers to: - A factor of 1024 (2 to the power of 10) as "k"
- 1024 squared (2 to the power of 20) as "M"
- 1024 cubed (2 to the power of 10) as "G"
The above units of computer memory are distinctly different from the metric abbreviations:- - k that stands for kilo and means thousand (1,000 or 10 to the power of
3) - M that stands for mega and means million (1,000,000 or 10 to the power
of 6) - G that stands for giga and means billion (1,000,000,000 or 10 to the power
of 9)
This is why units of computer memory should never be written out as "kilo", "mega" or "giga"Measurements
There should always be one blank space between a number and a unit (preferably a non-breaking space) Whenever possible, give numerical values in comparisons and explanations to avoid ambiguity: - Bad: Older hard drives were smaller.
- Better: Hard drives manufactured before 1999 had less than 1 GB of storage
capacity.
Only compare the value of items if they are of the same unit of measurement (i.e.: Don't compare apples to oranges). As a related matter, use the same units of measurement in comparisons. - Not so good: To compare and contrast the performance of this process on
an idle system with 256 MB, 512 MB and 1 GB of RAM... - Better: To compare and contrast the performance of this process on an idle
system with 256 MB, 512 MB and 1024 MB of RAM... - Exception: if the measurement remains the same and the unit changes, it
can be used for emphasis (e.g. it costs $10 per year where it used to cost about $10 per month)
Dates
Use the dd Mon yyyy format because it is less ambiguous, and globaly recognizable. Use a non-breaking space between the day and month, and between the month and year.Acronyms
Common acronyms - HTML: Hyper text markup language
- PC: Personal computer
- (ADD TO THIS LIST)
If an acronym is not in the above list it must be written out upon first usage and followed by the acronym in parenthesis - Example: Three letter acronyms (TLAs) are abundant in technical writing.
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