Style guides advise writers on the following issues:
1) Applying consistent standards: style guides’ objectives are to ensure consistency in a text or document and this can be achieved by following the same standards of writing, type of letter and vocabulary depending on the subject matter.
2) Citing sources: each style guide has a unique way to cite sources and special attention has to be pay when the writer uses a specific writing style. For example MLA style guide is commonly used in the United States when writing about humanities such as English Language and Literature. In this case, MLA guidelines provide a specific way to cite sources when writing.
3) Formatting text: style guidelines also provide instructions on which format should be used when writing, such as the size of the letter, how to underline titles, etc.