Yes. It's an American thing where a land developer has planned out a little town or neighborhood. There are walls and fences all the way around it, and a few places with gates (thus "gated community) and guards. The guards make sure that only people who live there, or have permission from people who live there, are allowed in. People who like them say that they give people a chance to choose a secure and peaceful place to live. People who don't like them say they create barricaded enclaves for the the moneyed elite, divert tax and other revenues from the surrounding communities, and create even deeper divisions between the rich and the middle and lower classes. (Note: if you think I sound like I'm in the second group, you're right.)

Supposedly modern, but not has modern as many wrongly believe. It only means a building or group of buildings where the only way in is through a gate or gates. A gated community in modern times began life as a marketing ploy by estate agents to encourage higher income earners into certain areas. The conflicts are caused because often these 'marketing gated communities' would be built or modified where previously there was are and open access to the poorer community noe suddenly overnight there is a gate prohibiting the local community from walking where they and their grandparents have walked for centuries. There are gated place in ancient towns not only for the rich but also the poor just to enclose a community and protect it.

Not really - from Wikipedia: In its modern form, a gated community (or walled community) is a form of residential community or housing estate containing strictly controlled entrances for pedestrians, bicycles, and automobiles, and often characterised by a closed perimeter of walls and fences.

apartment complex that has gates/ fence around it.