Completely private

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Sia splits apart, encrypts, and distributes your files across a decentralized network. Since you hold the keys, you own your data. No outside company can access or control your files, unlike traditional cloud storage providers.

Far more affordable

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Sia's decentralized cloud is on average 10x less expensive than current cloud storage providers. Storing 1TB on Sia costs about $2 per month, compared with$23 on Amazon S3. Calculate your savings below!
Highly redundant

Sia stores tiny pieces of your files on dozens of nodes across the globe. This eliminates any single point of failure and ensures highest possible uptime, on par with other cloud storage providers.

Open source

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Sia is completely open source. Over a dozen individuals have contributed to Sia's software, and there is an active community building innovative applications on top of the Sia API.
Marketplace on blockchain

Using the Sia blockchain, Sia creates a decentralized storage marketplace in which hosts compete for your business – this leads to the lowest possible prices. Renters pay using Siacoin, which can also be mined and traded.

Chek this video : https://youtu.be/B4YGpWxyn6Y