Good writers can switch gears. The way you write an email to a friend differs from how you'd write a business proposal. Understanding these differences makes you a versatile writer.
Formal writing uses longer words and complex sentences. Informal writing is conversational and uses everyday language. Neither is better - they're tools for different situations.
Academic Writing
This style values precision and evidence. You support claims with research. You avoid contractions and slang. You write objectively, presenting multiple viewpoints before drawing conclusions.
Creative Writing
Creative writing lets you be more personal and emotional. You can use metaphors, similes, and vivid descriptions. You're trying to evoke feelings, not just convey information.
Business Writing
This needs to be clear and efficient. Get to the point quickly. Use bullet points when possible. Respect your reader's time.