1) The word "triangle" contains four vowels: I, A, E, and E.

2) The Earth's core is primarily composed of iron and nickel and is as hot as the surface of the sun.

3) Aztec mythology, originating from ancient Mesoamerica, includes deities like Quetzalcoatl, Huitzilopochtli, and Tlaloc. It explores concepts of creation, sacrifice, and the cyclical nature of time, with intricate cosmology and rituals forming a significant part of Aztec religious beliefs and practices.

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