Salesforce.com and Force.com both are the cloud-based products and gives cloud-based services. Below I have explained in clear terms what the exact difference in both of them.

Salesforce.com:

• Salesforce.com is a SaaS product, SaaS stands for “Software-as-a-Service”. Dropbox, Google Apps, and GoToMeeting are the examples of the SaaS Products.
• Saleforce.com is a global cloud computing company. There is no requirement of the software for using the Salesforce but it is required to have a well-established internet connection and a browser.
• Salesforce.com is a web-based software product which runs on a Cloud platform. It allows the companies to manage their business relationships those are associated with them. Companies can track and manage their leads, contacts, accounts and the most important Sales Opportunities. 

• Force.com is PaaS product, PaaS is standing for “Platform-as-a-Service”. It is designed to develop cloud-based websites and applications using the IDE (Integrated Development Environment).
• Force.com is a platform which is used to create next-generation cloud applications. Applications available in “Salesforce App Exchange”, just like that applications Force.com also allows developers to build & deploy applications on the cloud.
• For creating any type of cloud-based applications, Force.com having many types of frameworks and development tools for them.  

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