Houses are constructions of wood, stone, or steel where people and sometimes their pets (such as cats and dogs) live. They are generally carefully constructed, although some parts of some cities have houses built with ad hoc or low quality materials.
Pretty much everyone has a house of some kind. The people who don't are known as homeless people, and while some of these people prefer not to have a house, the vast majority would like one. Why do so many people like houses? Well, a house offers privacy, protection from the elements, and a more secure place to keep goods than can generally be found out in the open. It is a good place to keep books, prepare food, kiss your boyfriend, or make a painting. It's easier to keep warm in winter than, say, a cave. Many offer connections to the internet, electricity, clean water, and sanitary methods of disposing of human waste.
One way a house might be dangerous is if it collapses in reaction to either a natural disaster or the aggregate forces of nature over time. If a person is in or near a house when it collapses, that person might be harmed. Most houses do not collapse before they are eventually intentionally removed.
A good novel about houses is Housekeeping by Marilynne Robinson, which was first published in 1980. Housekeeping describes three generations of women and their relationships to houses, which the novel investigates as metaphors for the characters' relationships and their attitudes towards society's expectations for their behavior and goals.
Because they don't collapse that much and are otherwise considered desirable, we consider houses to be not dangerous.
