In the early days a home was simply some place that could be considered safe. While conceivably it could include a relatively inaccessible open space, more commonly it involved the use of a handy cave or similar. Over time it came to be focused on the idea of being a shelter from the elements, and therefore an enclosed space.
The problem with caves, however, it that they aren't always where you want them to be. So people learned to create enclosed spaces of their own that could stand in the open. Probably starting from an early equivalent of a lean-to, huts of one kind or another were created using whatever materials were at hand. And as mobility became an issue, solutions like Tipi's and tents were developed.
With the development of agriculture, the meaning of home changed again. It wasn't enough to provide shelter from the elements, it needed to provide space for possessions and tools as well. But there are limits to how big an otherwise unsupported roof can get. At some point additional support must be provided. Any number of approaches are possible, but the favored approach has almost always been walls. And adding walls leads to the creation of new rooms. With the arrival of agriculture, one room huts ceased to be enough. And rooms have become specialized to serve as Living Spaces, Storage Spaces, and Work Spaces. Home is no longer just a shelter, it is where we live, sleep, and sometimes work. So what kinds of rooms can exist? Try the following:
Depending on circumstances, other rooms may exist as well, each serving some specialized purpose or activity. And as communities have become more closely organized, the idea of home has expanded to include not just a house, but possibly yards and gardens as well. For many people, home is a microcosm of how they would like the world to be organized, and they get to live in it. The rest of us are still working on it.