However, if you have a large number of records to process, you may wish to use Bulk API, which is based on REST principles and optimized for large sets of data.
Its advantages include ease of integration and development, and it’s an excellent choice of technology for use with mobile applications and Web projects. REST API provides a powerful, convenient, and simple REST-based Web services interface for interacting with Salesforce. These include the SOAP API, Apex, and Visualforce. When this is the case, the platform includes a number of ways for advanced administrators and developers to implement custom functionality.
However, your organization may have complex business processes that are unsupported by the existing functionality. In addition, Salesforce provides the ability to customize the prebuilt applications to fit your organization. The Salesforce prebuilt applications provide powerful CRM functionality. Use SOAP API in any language that supports Web services. With more than 20 different calls, SOAP API also allows you to maintain passwords, perform searches, and much more.
Use SOAP API to create, retrieve, update or delete records, such as accounts, leads, and custom objects. My intention is to help newbies with Real Time Example which I explained Below. The different Types of Salesforce API’s are mentioned below and you can also get the same info from Salesforce Help material.