What is Decentraland?

A simple question with a lot of different answers.

Decentraland is "A virtual world that runs on open standards."

For the "virtual world" part think of an experience (eventually) like those in a massive multiplayer online role playing game . For the open standards part of the definition, think of the underlying standards that power the internet, like HTTP for example.

and

"Decentraland is a virtual reality platform powered by the Ethereum blockchain. .

They key point here is that Decentraland is a "platform", i.e. a foundation or infrastructure that can be built upon. Decentraland is not the final product, it is the basis/platform/foundation that can be built upon.

The use of the Ethereum blockchain will allow Decentraland to not be controlled by a centralized organization, hence the "decentralized" part of the name.

"Users can create, experience, and monetize content and applications."

The users of decentraland will be able to:

create - contribute to the VR world, by for example owning "land" and placing a 3D rendered object there
experience - imagine traversing the VR world and interacting with objects/locations created within it
monetize - build chargeable services (again based of blockchain technology), providing an incentive for developers / business to invest in decentraland