Haemophilia, or hemophilia[6] (from Ancient Greek ¦Á?¦Ì¦Á (ha?ma) 'blood', and ¦Õ¦É¦Ë?¦Á (phil¨ªa) 'love of'),[7] is a mostly inherited genetic disorder that impairs the body's ability to make blood clots, a process needed to stop bleeding.[2][3] This results in people bleeding for a longer time after an injury, easy bruising, and an increased risk of bleeding inside joints or the brain.[1] Those with a mild case of the disease may have symptoms only after an accident or during surgery.[1] Bleeding into a joint can result in permanent damage while bleeding in the brain can result in long term headaches, seizures, or a altered level of consciousness.[1]

Reference
Wiki: Hemophilia