Question: What is (are) Bell's Palsy ?
Answer: Bell's palsy is a form of temporary facial paralysis resulting from damage or trauma to the 7th cranial nerve, one of the facial nerves. It is the most common cause of facial paralysis. Generally, Bell's palsy affects only one side of the face, however, in rare cases, it can affect both sides. Symptoms usually begin suddenly and reach their peak within 72 hours, and can range in severity from mild weakness to total paralysis. Symptoms vary among individuals and include sudden weakness on one side of the face, drooping eyelid or corner of the mouth, drooling, dry eye or mouth, altered taste, and excessive tearing in the eye. Bells palsy can cause significant facial distortion. The exact cause of Bell's palsy isn't known, but many scientists believe that reactivation of a dormant viral infection can cause the facial nerve to swell and becomes inflamed. Several other conditions can cause facial paralysis that might be diagnosed as Bell's palsy..
Source: NINDS

Question: What is the outlook for Bell's Palsy ?
Answer: The prognosis for individuals with Bell's palsy is generally very good. The extent of nerve damage determines the extent of recovery. With or without treatment, most individuals begin to get better within 2 weeks after the initial onset of symptoms and recover some or all facial function within 3 to 6 months.
Source: NINDS