Proportional representation systems differ from winner-takes-all systems primarily in how electoral votes are distributed. In proportional representation, parties gain seats in the legislature proportional to the number of votes they receive, allowing for a more diverse representation of political views. This system is often seen in multi-party systems and encourages smaller parties to participate. Conversely, in winner-takes-all systems, the candidate or party with the majority of votes in a district wins all available seats, potentially leading to a two-party system and marginalizing minority viewpoints. Each system has distinct implications for representation and political dynamics.