1) International relations encompass the study of relationships between nations, including diplomacy, treaties, and foreign policy. It examines the interactions and dynamics among different countries in the global arena.

2) The first commercially successful video game was "Pong," released in 1972 by Atari.

3) The Sydney Opera House, situated in Sydney, Australia, is an iconic architectural masterpiece and a UNESCO World Heritage site. Its unique design, resembling sailboats or shells, has made it one of the most recognized and photographed landmarks in the world.

4) The baguette, a long and crusty bread loaf, is synonymous with French culinary culture. It is a staple in French bakeries and is characterized by its crisp exterior and soft, airy interior. The baguette is typically made from wheat flour, water, yeast, and salt and is traditionally shaped by hand. It is enjoyed fresh and is a popular accompaniment to meals, sandwiches, and cheese platters, adding a touch of elegance and tradition to the dining experience.