1) The Epic of Gilgamesh, originating from ancient Mesopotamia, is one of the oldest surviving works of literature and tells the story of the heroic king Gilgamesh and his quest for immortality. It explores themes of friendship, mortality, and the relationship between humans and the divine.

2) 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.

3) The concept of proportional representation, used in some electoral systems, aims to ensure that political parties' representation in government aligns more closely with the proportion of votes they receive from the electorate.

4) The concept of self-driving cars, or autonomous vehicles, is being actively developed by companies such as Tesla, Google (Waymo), and Uber.