TL;DR
Mastodon is a decentralized, open-source microblogging network founded in 2016 that uses independently run servers (instances) connected across a ‘Fediverse’. Users pick a server when signing up, can communicate across servers, and manage privacy and moderation largely at the community level.
What happened
Mastodon, created in 2016 by Eugen Rochko, gained wider public attention after Elon Musk’s acquisition of Twitter and its rebrand to X, when many users sought alternatives. Unlike centralized social networks, Mastodon runs as a federated, nonprofit service: anyone can run a server (also called an instance) that joins the wider network. When you register on a server you receive an address such as @username@servername and can interact with users on other servers unless those servers are blocked. Instances set their own sign-up rules and moderation policies; some are open, others invite-only or require verification. The platform is open source, letting anyone inspect, modify or host the software. Mastodon supports familiar microblogging actions (posts, replies, boosts, bookmarks, hashtags), media attachments with size limits, timeline types (Home, Local, Federated), and post visibility controls.
Why it matters
- Decentralization shifts control from a single company to many communities, affecting moderation and user experience.
- Open-source code lets third parties host, modify or audit the software, increasing transparency and customization options.
- Server-level moderation means users can choose communities that match their safety and content preferences.
- Smaller, more focused communities can produce different conversational dynamics than large centralized platforms.
Key facts
- Founded in 2016 by German developer Eugen Rochko as a nonprofit project.
- Described as a federated network that operates similarly to email, not via blockchain.
- Users pick a server (instance) at signup; addresses look like @username@servername.
- Servers can block other servers, which prevents cross-server interaction with those instances.
- Common microblogging features are supported: posts, replies, boosts (retweets), favorites, bookmarks and hashtags.
- Quote-tweet–style feature was added in 2025.
- Media limits: up to four images (8 MB each); audio and video allowed but limited to 40 MB file size.
- Post visibility options include public, unlisted, followers-only, and mention-only.
- No universal verification system; some servers may vet sign-ups or require proof for membership.
What to watch next
- Whether Mastodon’s user base grows enough to change how intuitive the platform feels — not confirmed in the source.
- If more developers join the project and how that affects scalability and feature development — not confirmed in the source.
- Any moves toward a universal verification system or cross-instance moderation standards — not confirmed in the source.
Quick glossary
- Federation (Fediverse): A network of independently run servers that communicate with each other so users on different servers can interact.
- Instance / Server: An individual Mastodon community run by an admin or organization with its own rules and moderation policies.
- Open source: Software whose source code is publicly available for anyone to inspect, modify, and redistribute under its license.
- Boost: Mastodon’s equivalent of a retweet: sharing someone else’s post to your followers.
- Local vs Federated timeline: Local shows posts from users on your server; Federated shows public posts from accounts followed by people on your server.
Reader FAQ
How do I create a Mastodon account?
Go to Mastodon’s site, choose Create Account, pick a server by filtering region, language, topic or speed, and sign up; Mastodon also offers an easy option to create an account on mastodon.social.
Can I follow and message people on other servers?
Yes. You can follow and reply to users on other servers, but to follow someone on another server you must enter their username on your server to find them.
Is Mastodon safer than Twitter?
The source says safety depends on choices: users can join servers with stricter moderation and use built-in features to limit discovery, but overall safety varies by instance and settings.
Can I post privately?
Yes. When writing a post you can set its visibility to public, unlisted, followers-only, or only visible to mentioned users.
Is there a verified badge on Mastodon?
There is no universal verification system; some servers may vet sign-ups, but a global verification system is not present.
Unless if you’re really in the know about nascent platforms, you probably didn’t know what Mastodon was until Elon Musk bought Twitter and renamed it X. In the initial aftermath…
Sources
- A beginner’s guide to Mastodon, the open source Twitter alternative
- What to know about Mastodon, the Twitter alternative
- What Is Mastodon? Your Guide to the Decentralized Social …
- A beginner's guide to microblogging on Mastodon
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