Learn about the fundamental principles of electric circuits, including voltage, current, resistance, and common components like wires, batteries, and switches.

A carefree girl dances and twirls near the beach, enjoying the sun and sea breeze.

记录了夕阳下田园风光的美丽景象，晚霞、金黄色的小草和摇曳的狗尾草，伴随着晚风，展现了一片宁静而美丽的乡村景色。

Explore the incredible defense system of the human body, from the different jobs and components of the immune system to its response to infections and how it keeps you safe.

President Joe Biden delivers remarks at the Right to Unite for a Livable Future event, discussing workers' rights and labor unions.

Footage of a bearded astronaut walking on the Moon's dark side, holding a shiny sample container during a lunar mission.

German Chancellor Angela Merkel is seen eating spaghetti in a rare casual moment, showcasing her down-to-earth personality.