History of APIs - Salesforce.com
February 7th, 2000 Salesforce.com officially launched at the IDG Demo 2000 conference.
Salesforce.com launched its enterprise-class, web-based, sales force automation as a "Internet as a service". XML APIs were part of Salesforce.com from day one. Salesforce.com identified that customers needed to share data across their different business applications, and APIs were the way to do this.
Marc R. Benioff, chairman and founder of salesforce.com stated,"Salesforce.com is the first solution that truly leverages the Internet to offer the functionality of enterprise-class software at a mere fraction of the cost."
Salesforce.com was the first cloud provider to take an enterprise class web application and API and deliver what we know today as Software-as-a-Service.