What type of optical disc is commonly used to store digital data?

The correct choice is the Compact Disc (CD), which is a type of optical disc that has been widely used to store digital data. CDs were introduced in the early 1980s primarily for music storage, but they quickly became a popular medium for data storage due to their capacity to hold up to 700 MB of data. Their standard format allows for easy playback and reading by various devices, such as CD-ROM drives, making them accessible for consumers and organizations alike.

While DVDs and Blu-ray discs are also optical disc formats capable of storing digital data, they were developed later and offer greater storage capacities than CDs. DVDs can typically store around 4.7 GB of data, while Blu-ray discs can hold 25 GB or more. However, the question specifically inquires about the type commonly used to store digital data, where the CD holds historical significance as one of the first formats to achieve widespread adoption.

Flash memory, although a valuable data storage solution, is not categorized as an optical disc; instead, it is a form of solid-state storage that uses semiconductor technology to store data electronically, distinguishing it from optical media formats like CDs, DVDs, and Blu-ray discs.