Making a typographical error in an email, such as misspelling a professor's name, is a common occurrence and typically not a major issue. It's suggested that sending a brief follow-up email to apologize for the mistake can demonstrate conscientiousness rather than carelessness. Most professors are unlikely to notice or be bothered by such minor errors, and it's important to approach the situation with a relaxed mindset. Overall, this type of mistake is seen as trivial and manageable, emphasizing that everyone makes errors in communication.