Phase 4: Basho (Scaling Era)
The main feature of Basho is that it will bring sidechains to Cardano. This will help the network to scale so that it can handle significantly more transactions per second.
Sidechains are a way for transactions to happen on a side network that’s separate from the main Cardano base layer. The way a sidechain usually works is that transactions take place on a sidechain. Periodically, all of these transactions will be batched together and validated on the main chain. Because the transactions are happening on the sidechain, they remain unaffected by congestion on the main chain.
In terms of an analogy, a sidechain is like a road running next to a highway (the main chain). Cars can drive along the road (sidechain), and then at periodic intervals, they can access the highway via an onramp. There can be multiple sidechains running alongside the Cardano highway, and they can be customized to support different design requirements.