Most of what Closet Genious says is correct; unless you have some kind of medical problem, you don't need a special diet to lose weight. You just need to consume fewer calories than you burn. A high fat diet won't necessarily cause weight loss.
Macros (fat, protein, and carbs) can, however, affect how easily you maintain your diet. I for example would struggle to stick to a high fat or low carb diet because I feel most satiated on a high fiber (high complex carb) diet. I lost 18 lbs. eating almost nothing but oat bran, brown rice, potatoes, and vegetables every day. I am a mesomorph and I lift weights, so eating low protein doesn't affect my muscle mass much.
Basically, you have to figure out what is easiest for you: do you feel satisfied eating lots of fat? What is your body type, your medical and nutritional needs? Like I said, though, these considerations make the diet easier; to actually make it work (to lose weight) you simply need a caloric deficit. People have lost weight on junk food diets.
