Salesforce API integration provides programmatic access to the information of your organization with the use of powerful, secure yet simple application programming interfaces. This document can be used with the help of basic familiarity that you have with software development, Salesforce user interface and web services. The different functionality of the business is available to your organization if it is enabled with API feature. These features have been enabled by default for developer editions, enterprise, unlimited and performance. Salesforce API integration is also known as Enterprise API for people who prefer web services. It is used for updating and creating invoices and credit notes. You can also access to the core business processes of your business and also to the calculation engines that can generate valid debit and credit entries in your transaction module with appropriate balancing entries, tax calculations, currency and analysis applied. This process is also called posting which is a very important business process operation. Salesforce and API integration enables you to manipulate the records that represent certain objects like payable invoice and sales invoice. It is specifically done with enterprise web services API methods or Apex DML. This provides a very good opportunity for new developers for API record manipulation operations, update and create. There are different kinds of API that for used in an organization. SOAP AP SOAP AP is a prebuilt Salesforce application that provides a powerful functionality of CRM and the integration of API and Salesforce enables you to customize the prebuilt applications for meeting the needs of an organization. You can implement custom functionality if your organization has complex business processes. You can also use it for retrieve or create, delete or update records like custom objects and leads. It is optimized for the real time client applications that help in updating small records at one time. REST API REST API provides you with a convenient, powerful and simple REST that is based on web services interface for interaction with Salesforce. The advantage of this kind of API is that is can be integrated and developed easily and this technology can be used with web projects and mobile applications. BULK API BULK API is based on the principle of REST API that has been optimized for a larger set of data. It can load or delete a large set of data as it can also be used to query, update, insert or delete a very large number of records. You have to submit the batches of the records which are processed by Salesforce in the background. It has been designed to make the process simple for processing data. Metadata API Metadata API is used to deploy, retrieve, update, create and delete customizations for your organizations. It is intended for building tools and managing customizations that manages the metadata model and not the data. APEX REST API APEX REST API is similar to REST API as it enables you to do updates as they are on individual records. It helps you to contact data, send account or make updates with Salesforce API integration.