In web3, after building our smart contracts, frontend integration is required to make them interact with users like in web2.

To develop a web application that can interact with a Ethereum smart contract, we need 2 things about that smart contract:

• Address: When the smart contract is deployed to a blockchain, bytecode (binary data) is stored on the blockchain and an address is allocated to this contract. With this address, the smart contract stored in the blockchain can be accessed.
• ABI (application binary interface)

However, in Solana we need two main things:

• Provider: Solana Blockchain Provider is basically a wrapper around the Solana JSON RPC API making it easier to interact with the Solana Blockchain.
• Program Id: Id of the program in a network.

The Solana-Web3.js library which gives a convenient interface for the RPC methods aims to provide comprehensive Solana coverage. Using Solana web3.js it is possible to develop frontend with programming languages such as React, JavaScript, TypeScript and integrate it into a smart contract.

You can find detailed further information from Solana Official documentation: https://docs.solana.com/developing/clients/jsonrpc-api 

You can find the full documentation for the @solana/web3.js library here: https://solana-labs.github.io/solana-web3.js/