Blu-ray discs are a type of optical disc used for storing high-definition video and data. They were developed to provide better picture and sound quality than traditional DVDs. With a larger storage capacity, a single Blu-ray disc can hold up to 25 gigabytes of data for a single layer and 50 gigabytes for a dual layer, making it ideal for movies, games, and other media. To play a Blu-ray disc, you need a Blu-ray player, which is designed to read the disc's data. Many modern gaming consoles, like the PlayStation, also support Blu-ray playback. This technology has become popular for home entertainment, offering a more immersive viewing experience.