If you want to backup a large amount of data, the Seagate One Touch SSD 500GB, Green external drive is exactly what you need, giving you a whopping 500 GB of space. This makes the drive big enough to store thousands of holiday photos and videos. 2.5" drives are designed mostly for all minimalists and users who like to pack up a lot in as little space as possible. SSD is short for Solid State Drive, i.e. a flash-based drive. Unlike the standard HDD, this type is notably faster and will survive shocks and rough handling. This Seagate external drive uses USB 3,2 Gen 1 (USB 3,0) interface.