The movement of the hard drive's read/write heads over different areas of the disk when accessing fragmented files is slower, compared to accessing the entire contents of a non-fragmented file sequentially without moving the read/write heads to seek other fragments.
The giant oceanic manta ray can grow to a disc size of up to 7 m (23 ft) with a weight of about 1,350 kg (2,980 lb) but average size commonly observed is 4.5 m (15 ft). It is dorsoventrally flattened and has large, triangular pectoral fins on either side of the disc.
Manta Rays are similar to whale sharks, they are both plankton feeders and are migratory animals. If you join a whaleshark snorkel tour in Cancun then you will be sure to encounter these huge creatures along the way. A giant manta ray can grow up to 9 mts but they tend to be smaller in these waters.