Move reusable business logic into injectable classes that NestJS can create and share for you.
Providers are classes or values that NestJS can manage through its dependency injection system. Services are the most common type of provider, and they are usually where business logic lives.
A provider can be injected into controllers, other providers, or other parts of your application. NestJS also supports custom providers, which lets you control exactly how a dependency is created or what value should be provided.
What you'll walk away knowing