Social media has huge problems with free speech and moderation. Could decentralised platforms fix this?

Over the past few months, Twitter took down the account of the then-President of the United States and Facebook temporarily stopped users from sharing Australian media content. This begs the question: do social media platforms wield too much power?

Whatever your personal view, a variety of "decentralised" social media networks now promise to be the custodians of free-spoken, censorship-resistant and crowd-curated content, free of corporate and political interference.

But do they live up to this promise?

Cooperatively governed platforms

In "decentralised" social media networks, control is actively shared across many servers and users, rather than a single corporate entity such as Google or Facebook.

This can make a network more resilient, as there is no central point of failure. But it also means no single arbiter is in charge of moderating content or banning problematic users.

Some of the most prominent decentralised systems use blockchain (often associated with Bitcoin currency). A blockchain system is a kind of distributed online ledger hosted and updated by thousands of computers and servers around the world.

And all of these plugged-in entities must agree on the contents of the ledger. Thus, it's almost impossible for any single node in the network to meddle with the ledger without the updates being rejected.

Gathering 'Steem'

One of the most famous blockchain social media networks is Steemit, a decentralised application that runs on the Steem blockchain.

Because the Steem blockchain has its own cryptocurrency, popular posters can be rewarded by readers through micropayments. Once content is posted on the Steem blockchain, it can never be removed.

Not all decentralised social media networks are built on blockchains, however. The Fediverse is an ecosystem of many servers that are independently owned, but which can communicate with one another and share data.

Mastodon is the most popular part of the Fediverse. Currently with close to three million users across more than 3,000 servers, this open-source platform is made up of a network of communities, similar to Reddit or Tumbler.

Users can create their own "instances" of Mastodon - with many separate instances forming the wider network - and share content by posting 500-character-limit "toots" (yes, toots). Each instance is privately operated and moderated, but its users can still communicate with other servers if they want to.