1) The Age of Exploration, during the 15th and 16th centuries, saw European explorers such as Christopher Columbus and Vasco da Gama reach new lands and establish trade routes.

2) The development of the World Wide Web Consortium (W3C) and web standards has ensured interoperability and compatibility across different web browsers and devices.

3) The role of the media in politics is to provide information, analysis, and scrutiny of government actions, policies, and public affairs, serving as a watchdog and facilitating public discourse and transparency.

4) The ozone layer, located in the Earth's stratosphere, protects us from harmful ultraviolet (UV) radiation.