If you were a customer under sea looking for a good "shark" like you look for a dress in a market; you would have been thoroughly confused with the variety given to you. There are over 460 known species of sharks, and they come in all shapes and sizes. From huge Whale Shark, to small Spined Pygmy Shark, from lethargic Sleeper Sharks to fastest swimmers Shortfin Makos; one may find all kind of sharks, each adapted to its own peculiar niche in the sea. There are, for instance, flat-packed angelsharks that hug the sea bed, torpedo-bodied blue sharks that wander the open ocean, weird-looking goblin sharks with long, pointed snouts that dwell in the deep sea, eel-shaped frilled sharks, wobbegongs that resemble seaweed-encrusted rocks, highly-maneuverable hammerheads with bizarre-shaped heads, megamouths with cavernous mouths and thick lips, deep-sea sharks that glow in the dark and thresher sharks with amazingly long, scythe-shaped tails.

The Study of Shark Biology can be divided in to certain segments for better understanding of their adaptation to environment:

• Jaws and Teeth
• Digestive system
• Parasites and diseases
• Breathing
• Swimming