ELI5: Explain Like I'm 5

Illegal construction

Illegal construction is when someone builds something without permission from the government. In some cities and towns, you can't just build a house or other structure without asking the government first. The government has rules about how much space you can build on, what the building can look like, and other things like that. If you don't follow these rules, your construction can be illegal, and the government might make you take it down.