As you probably know already, solar power plants can be installed either on rooftops or can be located on the ground.
Rooftop solar power plants are typically of small to medium capacities, ranging from a few kWs to usually less than a MW. Ground-mounted projects, on the other hand can run from 1 MW to 100+ MW.
Conceptually, the large, ground-mounted solar farms are not any different from relatively smaller rooftop solar power plants.
They both generate solar power in a similar manner, and in both cases, the solar power gets converted from DC to AC by an inverter.
In the case of most ground mounted solar farms, the electricity generated is not used at the site, but instead, is transmitted through the electricity grid to be used in many different places.
Thus, ground mounted solar farms, especially large solar farms that are 100+ MW in size, are a centralized form of power generation, not very different from a coal or nuclear power plant in this context.
A rooftop solar power plant, on the other hand, is a distributed form of power generation, in which the power that is generated is consumed at, or very close to the point of generation. In this case hence, the electricity does not need the grid to be transmitted elsewhere.