and hard drive algorithms at the time were much more advanced than those of flash storage. Weighed less than a roll of 35mm film for cameras. Stored thousands of images (for cameras of that time). Sometimes sold with a PCMCIA adapter for laptops. A 4GB Microdrive is around 2700 1.44 MB floppy disks. Disadvantages As of 2006, Microdrive's capacity advantages were exceeded by CompactFlash cards (which are the same size and are often compatible with each other), and USB flash drives. As of 5 July 2015, 512GB CF cards are available, offering 42 times the storage space of the largest Microdrive. Being mechanical devices, they are more sensitive to physical shock and temperature changes than flash memory, though in practice they are very robust, and manufacturers have added several features to the more recent models to improve reliability. For example, a microdrive will generally not survive a 4-foot (1.2-meter) drop onto a hard surface whereas CF cards can survive much higher falls. Microdrives are not as fast as the high-end CompactFlash cards; they generally operate at around 4–6 megabytes per second while high-end CF cards can operate at 45 megabytes per second. This may cause problems for photographers who shoot sequences of large images in rapid succession. Also, they require some time to spin up when they have been idle (see below). They are not designed to operate at high altitudes (over 10,000 feet or 3,000 meters) but can be safely used on most commercial aircraft as cabins are generally pressurized. Only high-capacity models are manufactured, as it is not profitable to make low-capacity Microdrives. At the end of 2005 only capacities above 2GB are manufactured while 256MB and 512MB CompactFlash cards were still in production. Lower capacities are still readily available second hand on eBay but these are usually the same price as CF cards of the same size. Unlike flash storage, Microdrives require power even when no data is being transferred to or read from them, just to keep the disk spinning in order to maintain quick access. As a result, many devices such as the iPod mini leave the drive switched off for most of the time while periodically starting it up to fetch data from it to fill the device's buffer. Microdrives will switch off after idling for more than a few seconds to counter this problem; however, this means that it needs to spin up