A federal enclave is like a special area, just like a fort or a castle, but instead of being owned by a king or a queen, it is owned by the government of the entire country, called the federal government.
This special area is enclosed by a boundary, like a big fence, and usually includes government buildings or parks, and sometimes even entire cities or pieces of land that are owned by the government.
Because it is owned by the government, the laws that apply inside a federal enclave might be different from the laws outside the area. For example, the government might have their own rules for how people can use the land or what activities are allowed inside the enclave.
Overall, federal enclaves are places where the government has special ownership and control, with their own unique set of rules and procedures.