It is a multi-level structure designed to imitate a conventional house that a strata title owns. Which means you own the dwelling but share the land with other people.
Normally, the townhouses have privacy and scape of a normal house, so your family would be able to have enough space to move around, not only that, regularly come with an outdoor yard. Not only that, townhouses are bigger than an apartment, you can find often with two or even three-storeys townhouses.
Although, the body corporate still and, thus, has restrictions like an apartment.