Cloud computing continues to redefine the way in which organizations utilize information technology by providing increased flexibility, reduced cost of ownership and maintenance, massive scalability, and on-demand/pay-as-you-go services. Virtual and cloud technology replaces traditional IT products with services that can be purchased as-needed without the overhead of dedicated IT resources and staff. Public and private clouds are deployed using many different software platforms such as Eucalyptus, Xen, OpenStack, CloudStack and Amazon Web Services. This paper compares many popular cloud deployment platforms and related hypervisor technologies for implementing effective cloud-based computing services.