What are the main symptoms of obsessive compulsive disorder.

What are the main symptoms of this disorder? 2. what are the biological components of this disorder..talking about the brain. 3. what are the psychological burdens, including social, of this disorder. 4. in a more helpful fashion, what are good treatments for this disorder? there are often multiple options, many used together to treat the same person at times. need to have some journal references. use use psychological techniques