The document discusses 5 common errors in writing: 1) misspelling words, 2) beginning sentences without capitalization, 3) using texting abbreviations, 4) writing sentence fragments, and 5) run-on sentences. It provides examples of each error and explains why they should be avoided in academic writing and professional settings. The author emphasizes that developing good writing habits, such as proofreading and properly structuring sentences, is important for success in school and career opportunities.