Zapier is a tool that allows users to connect and automate different web applications. It allows users to create "Zaps", which are automated workflows between two or more apps. For example, you could use Zapier to automatically send new emails from Gmail to a Slack channel or to create new Trello cards from new rows in a Google Sheets spreadsheet.

To use Zapier, you first need to create an account and then select the apps you want to connect. Then you can set up your Zap by selecting a trigger (the event that starts the automation) and one or more actions (the tasks that are performed). For example, you could set up a Zap that is triggered when a new row is added to a Google Sheets spreadsheet, and the action would be to create a new card in Trello.

Zapier supports a wide range of apps, including popular ones like Google Sheets, Trello, Slack and Gmail. It is a powerful tool that allows you to automate many different types of tasks and workflows.