The last part of our Apex journey is a callout to a web service. You know that Twitter and Facebook, and even Salesforce, have a web service that you can connect with and grab the information you need. Some APIs are free to use, but for some information, you need to pay if you want to use or store that information.
For each secure web service, you need to authenticate to the service. This can be done in different ways and is dependent on the web service itself. Some easy APIs use only an API key, while other services use OAuth2.0 to authenticate.
The type of authentication should be found in the documentation of the API. Most of the time, you can find this documentation online, or contact the API vendor to receive this information.
In this book, we will use an API to get information about movies. There is an API called The Movie DB (https://www.themoviedb...