Italics are not just a way of emphasising words and terms. They can be used for titles of things, for example books, journals, plays, films, long poems, and legal cases; some foreign words and terms; the internal monologue of fictional characters; directions to the reader, such as see above; species of flora and fauna – and more!
What is italicised and what isn’t should be clearly defined and listed in a style sheet. The New Oxford Dictionary for Writers and Editors is a good place to start in thinking about what should and shouldn’t be italicised.
Remember that large blocks of italics are hard to read, so try and avoid the style of italicised indented quotes if it’s within your power to do so. Italics should also be used sparingly for emphasis…