PRESIDENTIAL GOVERNMENT	PARLIAMENTARY GOVERNMENT
DEFINITION
CHARACTERISTICS
DIFFERENCES
MERITS
DEMERITS

	UNITARY SYSTEM	FEDERAL SYSTEM
DEFINITION
CHARACTERISTICS
DIFFERENCES
MERITS
DEMERITS

	ABSOLUTE MONARCHY	CONSTITUTIONAL MONARCHY
DEFINITION
CHARACTERISTICS
DIFFERENCES
MERITS
DEMERITS

	AUTOCRATIC SYSTEM	DEMOCRATIC SYSTEM
DEFINITION
CHARACTERISTICS
DIFFERENCES
MERITS
DEMERITS

	AUTHORITARIANISM		TOTALITARIANISM
DEFINITION		DEFINITION
CHARACTERISTICS		CHARACTERISTICS
DIFFERENCES		DIFFERENCES
MERITS		MERITS
DEMERITS		DEMERITS

	OLIGARCHY		LIBERAL DEMOCRACY
DEFINITION		DEFINITION
CHARACTERISTICS		CHARACTERISTICS
DIFFERENCES		DIFFERENCES
MERITS		MERITS
DEMERITS		DEMERITS

Hope these simple tables could help our friends to note down some important 'points' on each type of government. From my experience, these tables help a lot in my Sem 1 and Sem 2 of DPA (AM). We don't have to memorize them, as all points are fact, we just have to be clear about them. And to be clear, we need a table, as simple as possible. Some may use mind-map. I used both though. 

I'm sorry I didn't fill in the blanks for you all. Because some may find other point which is more relevant for him / her to take into consideration, rather than just copying from others. I personally think doing research by ourselves can really improve our understanding, comparing to depending 100% on lecturer's note or friend's answer. They are good as reference, though. 

Good luck, my friends!