# Overview

Before you start building with the Nodefy API, it's helpful to understand the following core concepts:

### Webhooks

Webhooks are triggered when certain onchain events occur on the blockchain networks you're monitoring. These events could include:

* Token transfers
* Smart contract function calls
* NFT minting or sales
* ...and more

Nodefy lets you create webhooks to listen for these events, and when a webhook is triggered, it sends a notification to your users through the channels you have configured.

### Filters

Filters allow you to refine the conditions under which a webhook is triggered. You can specify criteria such as:

* Token type
* Transaction value
* Specific addresses or contract functions

By applying filters, you can ensure that notifications are only sent for the events that are truly relevant to your users.

### Actions

Actions are the steps taken when a webhook is triggered and its associated filters are met. Nodefy offers a variety of built-in actions, including:

* Sending email notifications
* Sending Telegram messages
* Posting to Slack channels
* Calling custom webhooks (for more flexibility building event-driven systems)

You can configure different actions for different webhooks, allowing you to tailor the notification experience to your specific needs.