Depending on who you ask, there are six rules for proper use of a comma or sixteen. Depending on who you ask, numbers should be written out or typed as numerals, or written out and then typed as numerals inside of parentheses.
Why? What’s up with these rules? What’s the point, and why all the changes?
Clarity and Emphasis
Writing is all about communication, so a huge chunk of the rules revolve around helping the reader understand what you’re trying to say, preferably without scratching their head about whether you’re talking about “a big ass-cannon” or “a big-ass cannon.”
The Oxford Comma is similar when you understand the reason for it. It’s not necessarily an issue when you’re listing three entirely unlike things (“I bought a potato, a shoe and a lollipop”), but when there’s any room for misinterpreting a sentence, the Oxford Comma can be vital.
When your writing is clear, you can focus on emphasizing the most important parts of what you’re saying.
For example, dropping numerals in the middle of words breaks up the flow and draws attention to the numbers, rather than the words. This is great in a scientific paper or a newspaper article, where the actual number is the most important part of the sentence (“the tests revealed a 3% growth” or “highway pileup leaves 30 wounded”). However, when the number isn’t all that important, writing it out lets it blend seamlessly into the rest of the text.
As Cyprith pointed out, though, writing out a number beyond two or three words can draw undue attention to the numbers themselves, sometimes to the point that the reader forgets what they’re supposed to be describing and why.
Are there any grammar rules that confuse you? Let us know in the comments!