From Academic Kids
Habitat is the place where a particular species lives and grows. It is essentially the environment—at least the physical environment—that surrounds (influences and is utilized by) a species population. We use "species population" instead of "organism" here because, while it is possible to describe the habitat of a single black bear, we generally mean not any particular or individual bear, but the grouping of bears that comprise a breeding population and occupy a certain geographical area. Further, this habitat could be somewhat different from the habitat of another group or population of black bears living elsewhere. Thus, it is neither the species, nor the individual, for which the term habitat is typically used. A microhabitat is the immediate surroundings and other physical factors of an individual plant or animal within its habitat.
However. the term "habitat" can be used more broadly in ecology. It was originally defined as the physical conditions that surround a species, or species population, or assemblage of species, or community (Clements and Shelford, 1939). Thus, it is not just a species population that has a habitat, but an assemblage of many species, living together in the same place that essentially share a habitat. Ecologists would regard the habitat shared by many species to be a biotope.
A biome is the set of flora and fauna which live in a habitat and occupy a certain geography.