This document discusses different types of business structures including sole traders, partnerships, private limited companies, and public limited companies. Private limited companies (LTDs) are typically small to medium in size and sell shares privately to friends and family, with the founder owning 50% of shares. Public limited companies (PLCs) are usually large businesses that sell shares to the public on stock exchanges, requiring a minimum of £50,000 capital to establish. Both LTDs and PLCs provide owners with limited liability for the amount they invested.