东欧, or Eastern Europe, refers to the region of Europe that includes countries such as 波兰, 捷克, 匈牙利, and the 斯洛伐克. This area is known for its rich history, diverse cultures, and significant political changes, especially during the 20th century. Many of these countries were part of the 苏联 or influenced by it during the Cold War. The geography of 东欧 features a mix of mountains, plains, and rivers, contributing to its varied climate. Economically, the region has transitioned from state-controlled systems to more market-oriented economies since the fall of communism in the late 20th century. Today, 东欧 is characterized by both challenges and opportunities as it integrates more with the rest of Europe.