Now-a-days, cloud computing becomes the most powerful tool to deliver data over the internet. Just by using web based tools data can be accessed anywhere, any time. But because of the proprietary services it is also having some restrictions. This encourages developers to modify it, and create an open source cloud computing platform, which is none other than open source cloud computing. It possess properties of both open source and cloud computing. This open source approach gives new meaning and new capability to cloud computing.