Research has found that US employees, on average, spend about a quarter of their time at work combing through the hundreds of emails each worker sends and receives each day.
And yet, according to career coach Barbara Pachter, plenty of professionals still don't know how to use email appropriately.
Pachter outlines modern email etiquette rules in her book "The Essentials Of Business Etiquette." We pulled out the most important ones you need to know.
Vivian Giang contributed to an earlier version of this article.