This chapter will introduce you to web3, and its related APIs and uses in Truffle. You will gain an understanding of the fundamentals of web3 and how it is used in Truffle to connect to and help develop blockchain and/or smart contract-based applications. Moreover, this chapter will give you a brief refresher about Solidity, including functions, data types, visibility specifiers, and events.

Specifically, you will:

• Learn and understand the reasons for the use of web3 in an isolated environment in Truffle
• Learn and understand the reasons for the use of web3 in Truffle
• Learn and understand the use of various types of functions and data types in Solidity
• Learn and understand when and why events are used
• Learn and understand how to use the appropriate type and visibility specifier when defining a function