Web application programming interfaces (API) play a major role in modern application development. They allow various third-party integrators to interact with applications through the HTTP layer. Magento supports both Representational State Transfer (REST) and Simple Object Access Protocol ( SOAP) APIs. Its web API framework is based on the create, read, update, delete (CRUD) and search (search criteria) models. The scope of functionality that APIs offer is quite big, allowing us to use them for a wide range of tasks, such as creating a completely new shopping application, integrating with customer relationship management (CRM) systems, enterprise resource planning (ERP) systems, and content management systems (CMS), as well as creating JavaScript widgets in the Magento storefront itself.

Moving forward, we are going to take a closer look at the following web API sections:

• Types of users
• Types of authentication
• Types of endpoints
• Using existing Web APIs
• Creating custom Web APIs
• Understanding search criteria