The team at Cosmos put together a series of different hands-on tutorials which will help you understand the inner-workings of the Cosmos SDK and Tendermint Core.
The Cosmos Academy is a developer-focused course which covers everything one needs to know about Cosmos and its ecosystem.
Protip: Before working through any of the tutorials you might want to watch the 45 minutes introductory talk "How to Build a Blockchain App with Cosmos SDK" by Jack Zampolin. This will help you understand the big picture and flow of information in a Cosmos-powered Blockchain.
- Cosmos
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Online series about the Cosmos ecosystem with interactive workshops and live coding sessions.