Events in Smart Contracts

In the final lesson, we'll learn about events in Solidity. Events allow notifying Ethereum users in real time about changes with a smart contract. We'll learn how to define events, send them, and subscribe to them programmatically.

Defining events

Before sending an event, we need to define what fields an event contains. Defining an event is similar to defining a struct. We need to use the event keyword, specify the event’s name, and then provide a list of fields each event will have. Event fields provide additional data we can send with each event.