The "SD-series" refers to a line of memory cards and storage devices that utilize the Secure Digital (SD) format. These cards are commonly used in cameras, smartphones, and other portable devices to store photos, videos, and data. The SD-series includes various types, such as SD, SDHC (Secure Digital High Capacity), and SDXC (Secure Digital eXtended Capacity), each offering different storage capacities and speed classes. The SD-series is designed to be compact and portable, making it easy to transfer data between devices. They are widely recognized for their reliability and compatibility with a range of electronics, including digital cameras, tablets, and laptops. The cards are also available in various capacities, allowing users to choose the right option for their storage needs.