The three main features of the Plum Pudding Model by J.J. Thomson are:Positive Sphere- The atom is described as a large sphere with a uniform positive charge, like a "pudding" or mass.Embedded Electrons - Negatively charged electrons are embedded and evenly distributed within the positive sphere, similar to "plums" in a pudding.Electrical Neutrality - The overall charge of the atom is neutral because the positive charge balances the negative charge of the electrons.