One issue closely related to formality is correctness. Correct writing is free of grammar, punctuation, style, usage, and spelling errors. Correctness problems occur most often in email and microblogs.

Some writers mistakenly think that they do not need to worry about correctness because these digital applications are meant for quick communication. They are wrong. You have to plan your digital correspondence just as you plan any other written communication, and you should revise, edit, and proofread it. Sending correspondence that contains language errors is unprofessional because it suggests a lack of respect for your reader—and for yourself. It also causes your reader to think that you are careless about your job.