What were the main differences between the articles of confederation and the constitution of 1787?

Based on my research the  Articles of Confederation was Americas first government.  A guiding principle of the Articles was to preserve the independence and sovereignty of the states. So in the Constitution is created the three branches of government therefore revising the Articles of Confederation. So the main different between he Articles of Confederation and the Constitution of 1787 were that "The federal government received o powers but the Constitution allowed giving people the power to choose the delegates and revising the first government."

Hope this helps!