1) Sourdough bread is a type of bread made through a fermentation process that involves wild yeast and lactic acid bacteria. It has a distinct tangy flavor and a chewy texture. Sourdough bread is often considered healthier than conventional bread due to its potential benefits for digestion and nutrient absorption. It has gained popularity in recent years, with artisanal bakeries and home bakers reviving the traditional art of sourdough baking.

2) The first photograph of a black hole was captured in 2019 using a network of telescopes around the world.

3) The average car has about 30,000 parts.

4) The world's oldest known recipe is for beer and is over 4,000 years old.