What type of storage device is similar to a floppy disk but capable of storing much more data coming in two capacities 100MB or 250MB?

The storage device you're referring to is a Zip disk. Developed by Iomega, Zip disks were designed to provide a higher-capacity alternative to floppy disks, offering storage options of 100MB or 250MB. They were widely used in the late 1990s and early 2000s for data backup and transfer before being largely replaced by USB flash drives and other modern storage solutions.