Punctuation is the name for marks used in writing. They are to help understanding and correct reading. The use of punctuation in English the best punctuation book pdf change from place to place and from time to time.
Modern typography suggests that punctuation should only be used when there is a need. That results in less punctuation than was the case the early 20th century. The use of these marks is often decided by a group or organization and then written down as a style guide.
If we work for an organization with a house style guide, then we use that guide. Punctuation helps the reader understand what is meant. He did not go to town because his father was absent.
This means he did not go to town, and the reason was not his father’s absence. He did not go to town, because his father was absent. This means he did not go to town, and the reason for not going was that his father was absent.
In the second example, no style guide will help. The writer just has to make sure that the sentence is understood as it is written. Punctuation is there to help the reader make sense of what is written.