The biggest reason small business owners choose to incorporate or form a limited liability company (LLC) legal structure is to protect themselves from the financial and legal liabilities associated with owning a business. Don't assume you can't incorporate just because you're a one-person operation-but do know that the IRS has specific rules set up to make sure small business owners don't abuse the system. Here's a look at the different forms of business corporations so you can make a S Corp vs. LLC vs. C Corp comparison.: