1) The concept of federalism involves the division of powers between a central government and regional or local governments, allowing for shared governance and autonomy for different levels of administration.

2) Greek mythology includes a wide array of gods and goddesses, such as Zeus, Poseidon, Athena, Aphrodite, and Apollo. These deities were believed to govern various aspects of life and the natural world and were often depicted with human characteristics and engaging in dramatic stories and conflicts.

3) The Cannes Film Festival, held annually in France, is one of the most prestigious film festivals in the world.

4) The first graphical web browser, Mosaic, was released in 1993 and played a key role in popularizing the World Wide Web.