ngrok is a tool that allows you to securely expose a local development server to the internet. This can be useful for testing webhooks and other integrations that require a publicly-accessible URL. With ngrok, you can create a secure tunnel to your local machine, which is assigned a unique URL that can be accessed from anywhere. This allows you to test and debug your code without having to deploy it to a public server.
Starting a server is as simple as running
ngrok http <port-number>