The goal of each atomic model was to accurately represent all of the experimental evidence about atoms in the simplest way possible.
J.J. Thomson developed what became known as the “plum pudding” model in 1904. Plum pudding is an English dessert similar to a blueberry muffin. In Thomson’s plum pudding model of the atom, the electrons were embedded in a uniform sphere of positive charge like blueberries stuck into a muffin. The positive matter was thought to be jelly- like or a thick soup. The electrons were somewhat mobile.
However, this model of the atom soon gave way to a new model developed by New Zealander Ernest Rutherford (1871-1937) about five years later.
A model gives an idea of what something looks like, but is not the real thing.
The “plum pudding” model of the atom consisted of a uniform sphere of positive charge with negative electrons embedded in the sphere.