An overview of Solana: scaling without sharding

While most next-generation blockchains are aiming to scale transaction throughput via sharding -- partitioning the validation work of the blockchain into smaller pieces (“shards”) -- Solana is trying to solve the problem on the base layer while keeping a single unified network.

The main reason to scale without sharding is because it breaks (or at least limits) the composability of smart contracts. One of the strengths of decentralized finance is composability, whereby developers are able to integrate with and easily build on the work of others.