Optical disc composed of a phase change material, most often AgInSbTe, an alloy of silver, indium, antimony, and tellurium. Optical discs are most commonly used for storing music (e.g. for use in a CD player), video (e.g. for use in a Blu-ray player), or data and programs for personal computers (PC). The Optical Storage Technology Association (OSTA) promotes standardized optical storage formats. Although optical discs are more durable than earlier audio-visual and data storage formats, they are susceptible to environmental and daily-use damage. Libraries and archives enact optical media preservation procedures to ensure continued usability in the computer's optical disc drive or
Picture disc many years later. These were deluxe picture discs, priced much higher than ordinary records, and they sold in very small numbers. In the early 1930s the entire record industry was being devastated by a worldwide economic depression and the proliferation of the new medium of radio, which made a wide variety of music available free of charge. Picture discs of all kinds were among the casualties. With the Great Depression and World War II no longer around to interfere with such modest luxuries, the picture disc reemerged in 1946, when Tom Saffardy's Sav-Way Industries began issuing Vogue Records. Vogues were