* Galaxies: These are massive collections of stars, gas, dust, and dark matter, held together by gravity. They can contain hundreds of billions of stars. Our own Milky Way galaxy is estimated to be about 100,000 light-years across.

* White Dwarf Stars: These are the dense, hot remnants of stars like our Sun after they have exhausted their nuclear fuel. White dwarfs are roughly the size of Earth, which is tiny compared to the vastness of a galaxy.

Imagine it like this:

Think of a single grain of sand. That's like a white dwarf star. Now imagine that grain of sand sitting inside a giant stadium filled with thousands of other grains of sand. That stadium would be like a galaxy.