What is blockchain development?
There are two main categories in my mind, either you build the infrastructure that runs blockchain-based networks or you build applications that run on top of these decentralized and permissionless networks. Of course, this differentiation doesn’t encompass all types of development on blockchains, but it is a good way to get started.
By blockchain infrastructure, people usually mean client implementations of blockchain protocols that nodes or validators run to keep the chains running. These clients are usually focused on distributed ledger technology, networking, virtual machines, and various other low-level types of engineering. The client is what enforces the rules of the blockchain protocol, runs the consensus mechanism, that executes all transactions in the network and makes sure all nodes are in sync, and more. This is also known as core blockchain development, which is not what most devs picture when thinking about blockchain or web3 development in general. There are various niches within blockchain development itself as well; you can focus on improving execution capabilities with technologies like rollups, validiums, or volitions, you can improve decentralization and security guarantees by innovating on the consensus layer of the protocol, etc.
There’s also blockchain infrastructure that supports the application layer by providing APIs to access blockchain data like oracles for smart contracts, indexing services for back ends, libraries that allow you to call and listen to smart contract events, decentralized storage services, and more.
The most popular type of blockchain development is on top of the application layer. Building decentralized applications (Dapps) can take many different forms, but it usually involves a smart contract and a user interface that interacts with that smart contract and listens to changes in the state of the blockchain. These applications can serve various use cases and can be used to build decentralized financial services, games, and so much more.
There are also applications that aggregate data from different smart contracts, transactions, and events on the blockchain to provide useful insight, these apps are mostly centered around data analysis and are not necessarily decentralized, but require an understanding of the underlying blockchain-based technologies.
If these concepts are completely foreign to you I suggest reading the how to get started section first, or Google the words you may not understand.