Decentraland is a Virtual World with limited space and Blockchain integrated into the virtual Real estate ownership. Land in Decentraland is permanently owned by the community, giving them full control over their creations. Users claim ownership of virtual land on a blockchain-based ledger of parcels. The MANA token can be used to purchase virtual land as well as other goods and services. 
Decentraland is a decentralized, virtual reality world in which players own the actual land within the world. Each plot of land is represented by a provably rare, unique ERC721 LAND token stored on the Ethereum blockchain. The owner of the ERC721 LAND token owns the corresponding land within the virtual world and grants them the ability to build whatever they'd like.
This concept is known as a Metaverse, “a collective virtual shared space, created by the convergence of virtually enhanced physical reality and physically persistent virtual space.” While this concept has been present in science fiction for quite some time, it is only now that the concept is coming to fruition. 
Within the Decentraland metaverse, users can navigate and interact with other people and entities within the world and claim ownership of virtual land. This land is finite and is identified by a series of coordinates within the virtual world. Developers and users can build anything they’d like on their claimed land, from 3D scenes to games. Because the platform is peer-to-peer, it is not susceptible to censorship by governments or other entities. 
The core ownership mechanism of Decentraland is an Ethereum smart contract that verifies the ownership of each parcel of land. Users can purchase any parcel of land in the world, so long as it is adjacent to another parcel of land. While LAND is a non-fungible asset within Decentraland, users can purchase LAND at a fixed cost of 1,000 MANA. MANA is a fungible ERC-20 token that was sold during the Decentraland ICO and has plans to continuously be sold to users in the near future. One unique mechanism of LAND registration is that the 1,000 MANA used to purchase the land are destroyed as a function of the LAND registry smart contract. 
In addition to being used for the purchase of LAND, MANA can be used to purchase services and items within the virtual world. 
Even though LAND is non-fungible, LAND will still be sellable and transferable much like real estate in the real world. Decentraland has partnered with district0x (cryptocurrency), to enable users to easily list, buy, and sell land on a decentralized marketplace (known as a district) through the district0x platform.
Decentraland has been compared to Second Life, a popular, centralized virtual world in which players can own land.
Initial Coin Offering
On Thursday, August 17th of 2017, Decentraland will have an Initial coin offering raising up to $20 million. The sale of the coin is made so the early purchasers of the coin have a discount, averaging 5% per day for the first week. The name of the coin is MANA, which can be exchanged for virtual land.
The Coin sale was scheduled to end one week after the launch, unless the $20 million cap were to be reached sooner. The latter proved to be the case.
When Decentraland's MANA coin had it's Initial Coin Offering, MANA sold out within 35 seconds. The people who were able to execute the trade had smart contracts in place. The entire offering was controversial because the coins were all owned by less than 3,000 buyers who quickly bought all the coins with pool contracts.
Many on Reddit and other similar Forums have expressed their discontent with the Initial Coin Offering. Decentraland's response was to reopen an offering at the original 40% discount at a future date. The users who would become eligible for purchasing the coin were signed up on Decentraland's whitelist.
Decentraland attempts to create a virtual reality metaverse, with a shared virtual world. Users can build whatever they want on their 3D land parcels. Decentraland sells units of LAND and coins of MANA. The price of 1 parcel of LAND (100m2) is 1,000 MANA.
There is no centralized owner of the land. Because of the limitations of the virtual world, users are encouraged to create districts or themed areas.
Early contributors receive discounts when purchasing the MANA coins, starting at 40% discount on the first day.
Stone Age — June of 2015 The Stone Age was a 2D implementation of Decentraland which served as a proof-of-concept. It enabled users to buy unique pixels on a 2D grid, change the color of those pixels, and transfer ownership of those pixels to others.
Bronze Age — Early 2017 The Bronze Age was a 3D implementation of Decentraland in which the blockchain stored the full content description of each parcel of land. A web demo is available that can be explored with or without a VR headset.
The Iron Age — Q4 2017 / Early 2018 The Iron Age will build upon the foundation of the Bronze Age by implementing the following features:
- P2P network for user interaction
- A micropayment system for the in-world economy
- A land management interface to develop, buy, rent, and sell LAND parcels
- A scripting language for programming experiences within the world